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Question 1
Correct
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A ‘claw hand’ is usually associated with injury to which of the following nerves?
Your Answer: Ulnar nerve
Explanation:A ‘claw hand’ is associated with injury to the ulnar nerve at the wrist affecting the interossei, lumbricals and hypothenar muscles of the hand. It is characterized by hypothenar eminence wasting, hyperextended metacarpophalangeal joints and flexed interphalangeal joints.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 2
Correct
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Increased resistance to flow of blood in cerebral vessels is most likely seen in:
Your Answer: Elevation in systemic arterial pressure from 100 to 130 mmHg
Explanation:Constant cerebral blood flow is maintained by autoregulation in the brain, which causes an increase in local vascular resistance to offset an increase in blood pressure. There will be an increase in cerebral blood flow (and decrease in resistance to cerebral blood flow) with a decrease in arterial oxygen or an increase in arterial CO2. Similarly, a decrease in viscosity will also increase the blood flow. Due to increased brain metabolism and activity during a seizure, there will also be an increase in the cerebral blood flow.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 3
Correct
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Which of the following factors will not affect the wound healing process in a young women who suffered serious burns to her chest and hands?
Your Answer: Vitamin A deficiency
Explanation:Healing can be sped-up or slowed down due to various reasons: 1. blood supply, 2. infection, 3. denervation, 4. collection of blood/hematoma, 5. mechanical stress, 6. foreign body, 7. techniques used during surgery and 8. dressing of the wound. Other systemic factors include 1. nutrition e.g. deficiency of zinc, vitamin C, protein deficiency, 2. metabolic status, 3. circulatory status and 4. hormonal influence
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 4
Correct
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Which of the following over-the-counter drugs can cause a prolonged bleeding time?
Your Answer: Acetylsalicylic acid
Explanation:Acetylsalicylic acid, or aspirin, is a nonsteroidal anti-inflammatory drug that is widely used as an analgesic and antipyretic. Aspirin is as a cyclo-oxygenase inhibitor that leads to decreased prostaglandin production. Decreased platelet aggregation is another effect of this drug, achieved by long-lasting use of aspirin.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 5
Incorrect
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What is the percentage of bone calcium that is freely exchangeable with the extracellular fluid that is available for buffering changes in the calcium ion balance?
Your Answer: 15%
Correct Answer: 1%
Explanation:Around 1% of calcium in the body is available for buffering changes in calcium ion balance. These are mainly derived from the bone that are freely exchangeable with extracellular fluid.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 6
Incorrect
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A 50-year old lady presented to the clinic with chronic pain in the abdomen. On physical examination, she was found to be pale. Further investigations revealed a decrease in both serum iron and total iron-binding capacity, along with an increase in serum ferritin. These findings are seen in:
Your Answer: Vitamin B12 deficiency
Correct Answer: Anaemia of chronic disease
Explanation:Anaemia of chronic disease is characterized by low serum iron, iron-binding capacity and saturation with increased ferritin (storage iron). Haemolytic anaemia is characterized by normal iron levels as the haemoglobin released from the haemolysed red blood cells is recycled. Anaemia due to chronic blood loss leads to low serum iron, low ferritin and high total iron-binding capacity (TIBC). Malabsorption, especially with duodenal involvement can also lead to iron deficiency anaemia with low ferritin and high TIBC. Megaloblastic anaemia due to vitamin B12 and folate deficiency is not associated with abnormalities in metabolism of iron.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 7
Correct
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An abdominal aortogram of a 59 year-old female with an abdominal aortic aneurysm shows occlusion of the inferior mesenteric artery. The patient, however, does not complain of any symptoms. Occlusion of the inferior mesenteric artery is rarely symptomatic because its territory is supplied by branches of the:
Your Answer: Middle colic artery
Explanation:The transverse colon is supplied by the middle colic artery which is a branch from the superior mesenteric artery. If the inferior mesenteric artery was occluded, branches from the middle colic may go to the marginal artery which supplies the descending colon, sigmoid colon and rectum.. Ileocolic and right colic arteries also branch from the superior mesenteric artery that supply the colon but the middle colic, which serves the more distal part of the colon is the better answer. The gastroduodenal artery branches off the common hepatic artery, which supplies part of the duodenum, pancreas and stomach. The splenic artery supplies the spleen, pancreas and curvature of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 8
Incorrect
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Which of the following is the cause of flattened (notched) T waves on electrocardiogram (ECG)?
Your Answer: Hyperkalaemia
Correct Answer: Hypokalaemia
Explanation:The T-wave is formed due to ventricular repolarisation. Normally, it is seen as a positive wave. It can be normally inverted (negative) in V1 (occasionally in V2-3 in African-Americans/Afro-Caribbeans). Hyperacute T-waves are the earliest ECG change of acute myocardial infarction. ECG findings of hyperkalaemia include high, tent-shaped T-waves, a small P-wave and a wide QRS complex. Hypokalaemia results in flattened (notched) T-waves, U-waves, ST-segment depression and prolonged QT interval.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 9
Correct
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Which of the following is the most likely cause of massive splenomegaly in a 35-year old gentleman?
Your Answer: Myelofibrosis
Explanation:Causes of massive splenomegaly include chronic myelogenous leukaemia, chronic lymphocytic leukaemia, lymphoma, hairy cell leukaemia, myelofibrosis, polycythaemia vera, sarcoidosis, Gaucher’s disease and malaria.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 10
Incorrect
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During a surgical procedure involving the carotid artery, which nerve in the cervical plexus of nerves that is embedded in the carotid sheath is most susceptible to injury?
Your Answer: Suprascapular nerve
Correct Answer: Ansa cervicalis
Explanation:The ansa cervicalis is a loop of nerves that are part of the cervical plexus. They lie superficial to the internal jugular vein in the carotid triangle. Branches from the ansa cervicalis innervate the sternohyoid, sternothyroid and the inferior belly of the omohyoid. The superior root of the ansa cervicalis is formed by a branch of spinal nerve C1. These nerve fibres travel in the hypoglossal nerve before leaving to form the superior root. The superior root goes around the occipital artery and then descends embedded in the carotid sheath. It sends a branch off to the superior belly of the omohyoid muscle and is then joined by the inferior root. The inferior root is formed by fibres from spinal nerves C2 and C3.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 11
Correct
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A 4-year-old child was brought to a paediatrician for consult due to a palpable mass in his abdomen. The child has poor appetite and regularly complains of abdominal pain. The child was worked up and diagnosed with a tumour. What is the most likely diagnosis ?
Your Answer: Nephroblastoma
Explanation:Nephroblastoma is also known as Wilms’ tumour. It is a cancer of the kidneys that typically occurs in children. The median age of diagnose is approximately 3.5 years. With the current treatment, approximately 80-90% of children with Wilms’ tumour survive.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 12
Incorrect
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Where does the ejaculatory duct open into?
Your Answer: Duct of the bulbourethral glands
Correct Answer: Prostatic urethra
Explanation:There are two ejaculatory ducts, one on either side of the midline. Each ejaculatory duct is formed by the union of the duct from the seminal vesicles with the ductus deferens. They start at the base of the prostate and run forward and downward between the middle and lateral lobes and along the side of the prostatic utricle to end in the prostatic urethra.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 13
Incorrect
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A 40 year old patient with an history of obesity has been diagnosed with meralgia parasthetica. The condition was discovered to be caused by the pinching of the lateral femoral cutaneous nerve. Injuries at what spinal levels usually affect this nerve?
Your Answer: L5, S1
Correct Answer: L2, L3
Explanation:The lateral femoral cutaneous nerve of the thigh arises from the dorsal division of the lumbar plexus of the second and the third lumbar nerves (L2 – L3). Spinal injuries at this level are likely to affect the lateral femoral cutaneous nerve. The lateral femoral cutaneous nerve innervates the skin on the lateral aspect of the thigh.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 14
Correct
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The vascular structure found on the right side of the fifth lumbar vertebra is?
Your Answer: Inferior vena cava
Explanation:The most likely vascular structure is the inferior vena cava. The inferior vena cava is formed by the joining of the two common iliac arteries, the right and the left iliac artery, at the level of the fifth lumbar vertebra( L5). The inferior vena cava passes along the right side of the vertebral column. It enters the thoracic cavity into the underside of the heart through the caval opening of the diaphragm at the level of the eight thoracic vertebra (T8).
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 15
Incorrect
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The following structures DO NOT lie between the layers of the mesosalpinx except for the?
Your Answer: Uterus
Correct Answer: Fallopian tube
Explanation:Mesosalpinx is the portion of the broad ligament that stretches from the fallopian tube to the ovary and contains the uterine tubes between it’s layers.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 16
Incorrect
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Which of the following is a likely cause of jaundice?
Your Answer: Haemolytic disease if plasma albumin is low and globulin high
Correct Answer: Hepatic disease if plasma albumin is low and serum aminotransferase elevations > 500 units
Explanation:Jaundice can occur due to any of the possible causes and treatment depends upon diagnosing the correct condition. Mild hyperbilirubinemia with normal levels of aminotransferase and alkaline phosphatase is often unconjugated (e.g., due to haemolysis or Gilbert’s syndrome rather than hepatobiliary disease). Moderate or severe hyperbilirubinemia along with increased urinary bilirubin (bilirubinuria), high alkaline phosphatase or aminotransferase levels suggest hepatobiliary disease. Hyperbilirubinemia produced by any hepatobiliary disease is largely conjugated. In this case, other blood tests include hepatitis serology for suspected hepatitis, prothrombin time (PT) or international normalised ratio (INR), albumin and globulin levels, and antimitochondrial antibody levels (suspected primary biliary cirrhosis). Low albumin and high globulin levels suggest chronic rather than acute liver disease. In cases where there is only a an elevation of alkaline phosphatase, γ-glutamyl transpeptidase (GGT) levels should be checked – the levels of which will be found high in hepatobiliary disease, but not in bone disorder which can also lead to elevated alkaline phosphatase levels. In diseases of hepatobiliary origin, aminotransferase elevations > 500 units suggest a hepatocellular cause, whereas disproportionate increases of alkaline phosphatase (e.g., alkaline phosphatase > 3 times normal and aminotransferase < 200 units) suggest cholestasis. Because hepatobiliary disease alone rarely causes bilirubin levels > 30 mg/dl, higher levels are suggestive of a combination of severe hepatobiliary disease and haemolysis or renal dysfunction. Imaging is best for diagnosing infiltrative and cholestatic causes of jaundice. Liver biopsy is rarely needed, but can be of use in intrahepatic cholestasis and in some types of hepatitis.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 17
Incorrect
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A 40-year old man sustained a deep laceration to the sole of his left foot. It was found that the belly of extensor digitorum muscle was lacerated and the lateral tarsal artery was severed. The lateral tarsal artery is a branch of the:
Your Answer: Peroneal artery
Correct Answer: Dorsalis pedis artery
Explanation:The lateral tarsal artery arises from the dorsalis pedis, as the vessel crosses the navicular bone
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 18
Incorrect
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A CT scan of 65 year old male patient at an outpatient clinic suggested a bone tumour at the stylomastoid foramen. Which of the following cranial nerves is likely to be affected with this tumour?
Your Answer: X
Correct Answer: VII
Explanation:Cranial nerve VII, the facial nerve, is found in the internal acoustic canal and runs through this canal into the facial canal before exiting through the stylomastoid foramen. In the case of a bone tumour at the stylomastoid process, the facial nerve is the nerve that will most likely be affected.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 19
Correct
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The muscle that stabilizes the stapes is innervated by which of the following nerves?
Your Answer: Facial nerve
Explanation:The stapedius is the smallest skeletal muscle in the human body. At just over one millimetre in length, its purpose is to stabilize the smallest bone in the body, the stapes and is innervated by a branch of the facial nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 20
Incorrect
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Which portion of the renal tubule absorbs amino acids and glucose?
Your Answer: Collecting duct
Correct Answer: Proximal convoluted tubule
Explanation:In relation to the morphology of the kidney as a whole, the convoluted segments of the proximal tubules are confined entirely to the renal cortex. Glucose, amino acids, inorganic phosphate and some other solutes are reabsorbed via secondary active transport in the proximal renal tubule through co-transport channels driven by the sodium gradient.
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This question is part of the following fields:
- Physiology
- Renal
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Question 21
Correct
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A 40 year old man from Japan was diagnosed with cancer of the oesophagus. He is to undergo esophagectomy. While mobilizing the oesophagus in the neck, for resection and anastomosis with the stomach tube on the left side, the surgeon must be cautious not to injure a vital structure. Which of the following is it?
Your Answer: Thoracic duct
Explanation:The oesophagus is divided into 3 portions: cervical (part that is in the neck), thoracic portion and the abdominal portion. The cervical part is bordered by the trachea anteriorly and the prevertebral fascia covering the bodies of the 6,7 and 8th vertebra posteriorly. The thoracic duct lies on the left side at the level of the sixth cervical vertebra. The carotid sheath with its contents and lower poles of the lateral lobes of thyroid gland are lateral. The thoracic duct is the structure most likely to be injured.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 22
Incorrect
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Which one of the following groups of lymph nodes is most likely to be inflamed due to paronychia involving the big toe?
Your Answer:
Correct Answer: Vertical group of superficial inguinal lymph nodes
Explanation:Paronychia affecting the big toe will result in inflammation of the superficial inguinal lymph nodes as it drains lymph from the big toe.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 23
Incorrect
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A patient who complained of pain on the lower left side of the back had an x-ray done which confirmed a hernia passing posterolaterally, just superior to the iliac crest. Where is this hernia passing through?
Your Answer:
Correct Answer: Lumbar triangle
Explanation:The lumber triangle is bound medially by the border of the latissimus dorsi, laterally by the external abdominal oblique and by the iliac crest inferiorly. This is exactly where the hernia that is described is located.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 24
Incorrect
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Which of the following structures is not easily palpable?
Your Answer:
Correct Answer: Styloid process of the temporal bone
Explanation:The styloid process is a thin, pointed process that projects antero-inferiorly from the base of the petrous temporal bone. It can vary in length from a short, stubby process to a slender, four to five centimetre rod. It forms from the cranial elements of the second pharyngeal arch. The tympanic plate of the temporal bone ensheathes the base of this process. The pointed, projecting portion of the process provides attachment to the stylohyoid and stylomandibular ligaments, and to three muscles – the styloglossus, stylohyoid, and stylopharyngeus. As the styloid process is covered by the various muscles, it is not easily palpable in live subjects.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 25
Incorrect
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The ability of the bacteria to cause disease or its virulence is related to :
Your Answer:
Correct Answer: Toxin and enzyme production
Explanation:The pathogenicity of an organism or its ability to cause disease is determined by its virulence factors. Many bacteria produce virulence factors that inhibit the host’s immune system. The virulence factors of bacteria are typically proteins or other molecules that are synthesized by enzymes. These proteins are coded for by genes in chromosomal DNA, bacteriophage DNA or plasmids. The proteins made by the bacteria can poison the host cells and cause tissue damage.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 26
Incorrect
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When conducting an exploratory laparotomy procedure of a patient diagnosed with a bleeding ulcer of the lesser curvature of the stomach, which artery in this patient are you most likely to ligate to control the bleeding?
Your Answer:
Correct Answer: Left gastric
Explanation:The lesser curvature of the stomach is supplied by the left gastric artery along with the right gastric artery. These two arteries are the ones to most likely be ligated if bleeding was to be stopped at the lesser curvature of the stomach. The splenic artery branches from the celiac branch and supplies the spleen. The left gastro-omental, the right and left gastroepiploic arteries supply the greater curvature.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 27
Incorrect
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Which one of the following muscles is innervated by the facial nerve?
Your Answer:
Correct Answer: Buccinator
Explanation:Buccinator is a muscle of facial expression and is therefore innervated by the facial nerve. The lateral pterygoid, masseter, anterior belly of digastric and temporalis are all muscles of mastication and therefore innervated by the mandibular division of the trigeminal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck; Neurology
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Question 28
Incorrect
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What best describes the muscles of the posterior compartment of the leg?
Your Answer:
Correct Answer: One of the posterior compartment leg muscles laterally rotates the femur
Explanation:The muscles of the back of the leg are subdivided into two groups: superficial and deep. Superficial muscles include gastrocnemius, soleus and plantaris and are the chief extensors of the foot at the ankle joint. Deep muscles include the tibialis posterior, flexor hallucis longus, flexor digitorum longus and popliteus
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 29
Incorrect
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An 8 year old boy presents with a history of repeated bacterial/pyogenic infections. He had a normal recovery from chickenpox and measles and shows normal antibody response. A decrease in which of the cell types can best explain this history of repeated pyogenic infections?
Your Answer:
Correct Answer: Neutrophils
Explanation:A decrease in the number of granulocytes, particularly neutrophils is known as agranulocytosis and it increases the susceptibility of an individual towards recurrent infections. Neutropenia can be either due to decreased production or increased elimination of neutrophils.
Ineffective agranulopoiesis is seen in: 1. myeloid stem cell suppression, 2. disease conditions associated with granulopoiesis such as megaloblastic anaemia and myelodysplastic syndromes, 3. rare genetic diseases, 4. splenic sequestration and 5. increased peripheral utilization.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 30
Incorrect
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Which of the following muscles attach to the hyoid bone?
Your Answer:
Correct Answer: Middle pharyngeal constrictor
Explanation:The hyoid bone is a horseshoe-shaped bone situated in the anterior midline of the neck between the chin and the thyroid cartilage. A large number of muscles attach to the hyoid: Superiorly – the middle pharyngeal constrictor muscle, hyoglossus muscle, genioglossus, intrinsic muscles of the tongue and suprahyoid muscles. Inferiorly – the thyrohyoid muscle, omohyoid muscle and sternohyoid muscle.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 31
Incorrect
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Which of the following foramen provides passage of the facial nerve?
Your Answer:
Correct Answer: Internal acoustic meatus
Explanation:The internal auditory meatus provides a passage through which the vestibulocochlear nerve, the facial nerve, and the labyrinthine artery (an internal auditory branch of the basilar artery) can pass from inside the skull to structures of the inner ear and face.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 32
Incorrect
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Cranial nerve XII, the hypoglossal nerve, innervates which one of the following muscles in the list?
Your Answer:
Correct Answer: Hyoglossus
Explanation:The cranial nerve XII, hypoglossal nerve, innervates all the intrinsic and extrinsic muscles of the tongue except the palatoglossus. The muscles of the tongue innervated by this nerve include the extrinsic muscles; hyoglossus, styloglossus, genioglossus and the intrinsic muscles; superior longitudinal, inferior longitudinal, vertical and transverse muscles. The salpingopharyngeus, palatoglossus and the palatopharyngeus muscles are innervated by the vagus nerve. The stylopharyngeus muscle is innervated by the glossopharyngeal nerve (CN IX). The mylohyoid muscle is innervated by the inferior alveolar nerve, a branch of the mandibular nerve. Finally, the geniohyoid muscle is innervated by the olfactory nerve (CN I) via the hypoglossal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 33
Incorrect
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The Brunner glands secrete an alkaline product that helps maintain an optimal pH for pancreatic enzyme activity. Where are these glands located?
Your Answer:
Correct Answer: Submucosa of the duodeneum
Explanation:The Brunner glands are located in the submucosa of the duodenum. These glands are connected to the interstitial lumen by ducts that open into certain crypts. They secrete an alkaline product that protects the duodenal mucosa from the acidic chyme and helps achieve an optimal pH for the enzymes.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 34
Incorrect
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A nerve is injured during a surgical operation to repair an inguinal hernia. It passes through the superficial inguinal ring. Which nerve is it most likely to be?
Your Answer:
Correct Answer: Ilioinguinal
Explanation:The ilioinguinal nerve doesn’t pass through the deep inguinal ring but enters the inguinal canal from the side and leaves by passing through the superficial ring thus it is at risk of injury during inguinal hernia repair.
The femoral branch of genitofemoral nerve travels lateral to the superficial inguinal ring.
The iliohypogastric nerve and the subcostal nerve travel superior to the inguinal canal and superficial inguinal ring.
The obturator nerve is a branch of the lumbar plexus that innervates the muscles of the thigh.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 35
Incorrect
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A young boy fell from a tree, sustaining an injury to the elbow area and damaging the nerve behind the medial epicondyle of the humerus. What is the most likely result from that injury?
Your Answer:
Correct Answer: Flexion in the distal interphalangeal joint of digit 5
Explanation:The nerve injured in this situation is the ulnar nerve. It passes posterior to the medial epicondyle of the humerus before going between the two heads of the flexor carpi ulnaris muscle. This nerve supplies the muscles and skin of forearm and hand. At the level of medial epicondyle, the injury will led to paralysis in flexor carpi ulnaris and the ulnar half of the flexor digitorum profundus as well as the palmar interossei and hypothenar muscles in the hand. The correct answer will be that the boy will suffer from inability to flex the distal interphalangeal joint of digit 5
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 36
Incorrect
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The proximal tubule is the portion of the ductal system of the nephron of the kidney which leads from Bowman's capsule to the loop of Henle. Which of the following is most likely to be seen in a sample of fluid leaving the proximal tubule?
Your Answer:
Correct Answer: It will have no amino acids
Explanation:The proximal tubule is the portion of the duct system of the nephron leading from Bowman’s capsule to the loop of Henlé. The most distinctive characteristic of the proximal tubule is its brush border (or ‘striated border’). The luminal surface of the epithelial cells of this segment of the nephron is covered with densely packed microvilli forming a border which greatly increases the luminal surface area of the cells, presumably facilitating their reabsorptive function. Glucose, amino acids, inorganic phosphate, and some other solutes are100% reabsorbed via secondary active transport through co-transporters driven by the sodium gradient out of the nephron.
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This question is part of the following fields:
- Physiology
- Renal
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Question 37
Incorrect
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A 31-year-old woman is diagnosed with adrenal hyperplasia, and laboratory samples are taken to measure serum aldosterone and another substance. Which is most likely to be the other test that was prescribed to this patient?
Your Answer:
Correct Answer: Plasma renin
Explanation:The evaluation of a patient in whom hyperaldosteronism is first to determine that hyperaldosteronism is present (serum aldosterone) and, if it is present, to differentiate primary from secondary causes of hyperaldosteronism. The aldosterone-to-renin ratio (ARR) is the most sensitive means of differentiating primary from secondary causes of hyperaldosteronism as it is abnormally increased in primary hyperaldosteronism, and decreased or normal but with high renin levels in secondary hyperaldosteronism.
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This question is part of the following fields:
- Physiology
- Renal
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Question 38
Incorrect
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After surgery, a patient developed a stitch granuloma . Which leukocyte in the peripheral blood will become an activated macrophage in this granuloma?
Your Answer:
Correct Answer: Monocyte
Explanation:Monocytes are leukocytes that protect the body against infections and move to the site of infection within 8-12 hours to deal with it. They are produced in the bone marrow and shortly after being produced are released into the blood stream where they circulate until an infection is detected. When called upon they leave the circulation and transform into macrophages within the tissue fluid and thus gain the capability to phagocytose the offending substance. Monocyte count is part of a complete blood picture. Monocytosis is the state of excess monocytes in the peripheral blood and may be indicative of various disease states. Examples of processes that can increase a monocyte count include: • chronic inflammation • stress response • hyperadrenocorticism • immune-mediated disease • pyogranulomatous disease • necrosis • red cell regeneration.
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This question is part of the following fields:
- General
- Physiology
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Question 39
Incorrect
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A surgeon ligates the left superior suprarenal artery whilst preforming a left adrenalectomy. Where does the left superior suprarenal artery originate?
Your Answer:
Correct Answer: Left inferior phrenic artery
Explanation:The superior suprarenal arteries arises from the inferior phrenic artery on either side.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 40
Incorrect
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Which of the following foramina will the ophthalmic artery pass through in order to reach the eye?
Your Answer:
Correct Answer: Optic canal
Explanation:The optic foramen is the opening to the optic canal. The canal is located in the sphenoid bone; it is bounded medially by the body of the sphenoid and laterally by the lesser wing of the sphenoid. The superior surface of the sphenoid bone is bounded behind by a ridge, which forms the anterior border of a narrow, transverse groove, the chiasmatic groove (optic groove). The groove ends on either side in the optic foramen, which transmits the optic nerve and ophthalmic artery into the orbital cavity. Compared to the optic nerve, the ophthalmic artery is located inferolaterally within the canal.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 41
Incorrect
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A 50 year-old man, who sustained a head injury experienced sudden onset of horizontal double vision. He is diagnosed with lateral rectus palsy. Which of the following nerves is affected in this condition?
Your Answer:
Correct Answer: Abducent
Explanation:The lateral rectus muscle is one of the 6 extra-ocular muscles that control eye movements. It is responsible for abduction and is the only muscle that is innervated by the abducens nerve (CN VI).
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 42
Incorrect
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A 34-year old gentleman presented with acute pancreatitis to the emergency department. On enquiry, there was found to be a history of recurrent pancreatitis, eruptive xanthomas and raised plasma triglyceride levels associated with chylomicrons. Which of the following will be found deficient in this patient?
Your Answer:
Correct Answer: Lipoprotein lipase
Explanation:The clinical features mentioned here suggest the diagnosis of hypertriglyceridemia due to lipoprotein lipase (LPL) deficiency. LPL aids in hydrolysing the lipids in lipoproteins into free fatty acids and glycerol. Apo-CII acts as a co-factor. Deficiency of this enzyme leads to hypertriglyceridemia.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 43
Incorrect
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A 38 year-old man falls on an outstretched hand. X-rays indicate an anterior dislocation of one of the carpal bones. Which carpal bone is most commonly dislocated?
Your Answer:
Correct Answer: Lunate
Explanation:The scaphoid bone is the most commonly fractured carpal bone and has an increased risk of avascular necrosis.
The lunate is the most commonly dislocated carpal bone. The displaced bone may compress the median nerve in the carpal tunnel.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 44
Incorrect
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A 14 year old girl suffers from haemophilia A and chronic knee pain with progressive swelling and deformity over the last 4 years. Test results reveal a significantly reduced factor VIII activity. Which of the following is seen in the knee joint space after an acute painful episode?
Your Answer:
Correct Answer: Cholesterol crystals
Explanation:Due to breakdown of the red blood cell membrane in haemophilic patients, cholesterol crystals are formed by the lipids. On the other hand lipofuscin deposition does not occur in haemolysis or haemorrhage. Neutrophil accumulation suggests acute inflammation. Anthracotic pigment is an exogenous carbon pigment that deposits in the lung from dust. Russell bodies are intracellular accumulations of immunoglobins in plasma cells. Curschmann’s spirals and Charcot Leyden crystals are pathognomonic of asthma.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Haematology
- Pathology
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Question 45
Incorrect
-
The muscle that forms the posterior wall of the axilla along with the scapula, subscapularis muscle and teres major muscle is the?
Your Answer:
Correct Answer: Latissimus dorsi
Explanation:The latissimus dorsi forms the posterior wall of the axilla along with the scapula. It is responsible for extension, adduction, transverse extension also known as horizontal abduction, flexion from an extended position, and (medial) internal rotation of the shoulder joint. It also has a synergistic role in extension and lateral flexion of the lumbar spine.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 46
Incorrect
-
Which of the following is likely to induce secretion of glucagon?
Your Answer:
Correct Answer: Low serum concentration of glucose
Explanation:The most potent stimulus for secretion of glucagon is hypoglycaemia whereas hyperglycaemia is a stimulus for insulin release. Glucagon secretion also occurs in response to high levels of amino acids. Somatostatin inhibits glucagon secretion. Parasympathetic stimulation increases pancreatic acinar secretion, but not of α-cells.
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 47
Incorrect
-
A diabetic 58-year-old man, after the injection of radiographic contrast, has a decreased urine output and decreased level of consciousness. Which of the following conditions has he most likely developed
Your Answer:
Correct Answer: Acute tubular necrosis
Explanation:Acute tubular necrosis (ATN) involves damage to the tubule cells of the kidneys and is the most common cause of acute kidney injury. ATN in the majority of the cases is caused by ischaemia of the kidneys due to lack of perfusion and oxygenation but it may also occur due to poison or harmful substance. Contrast used for radiology may cause ATN in patients with several risk factors e.g. diabetic nephropathy. Symptoms may include oliguria, nausea, fluid retention, fatigue and decreased consciousness.
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This question is part of the following fields:
- Pathology
- Renal
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Question 48
Incorrect
-
The extent of cancer growth can be described through staging. What is taken into consideration when staging a cancer?
Your Answer:
Correct Answer: Local invasion
Explanation:Cancer stage is based on four characteristics: the size of cancer, whether the cancer is invasive or non-invasive, whether the cancer has spread to the lymph nodes, and whether the cancer has spread to other parts of the body, in this case beyond the breast. Staging is important as it is often a good predictor of outcomes and treatment is adjusted accordingly.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 49
Incorrect
-
After a prolonged coronary artery bypass surgery, a 60-year old gentleman was transfused 3 units of fresh-frozen plasma and 2 units of packed red cells. Two days later, the nurse noticed that he was tachypnoeic and chest X-ray showed signs consistent with adult respiratory distress syndrome. Which of the following variables will be low in this patient?
Your Answer:
Correct Answer: Compliance of the lung
Explanation:Acute or adult respiratory distress syndrome (ARDS) is a reaction to several forms of lung injuries and is commonly associated with sepsis and SIRS (systemic inflammatory response syndrome), severe traumatic injury, severe head injury, narcotics overdose, drowning, pulmonary contusion, and multiple blood transfusions. There is an increase in risk due to pre-existing liver disease or coagulation abnormalities. It results due to indirect toxic effects of neutrophil-derived inflammatory mediators in the lungs. ARDS is defined by the 1994 American–European Consensus Committee as the acute onset of bilateral infiltrates on chest X-ray, a partial pressure of arterial oxygen (pa(O2)) to fraction of inspired oxygen Fi(O2) ratio of less than 200 mmHg and a pulmonary artery occlusion pressure of less than 18 or the absence of clinical evidence of left arterial hypertension. ARDS is basically pulmonary oedema in the absence of volume overload or poor left ventricular function. This is different from acute lung injury, which shows a pa(O2)/Fi(O2) ratio of less than 300 mmHg. Pathogenesis of ARDS starts from damage to alveolar epithelium and vascular endothelium, causing increased permeability. Damage to surfactant-producing type II cells disrupts the production and function of pulmonary surfactant, causing micro atelectasis and poor gas exchange. There is a decrease in lung compliance and increase in work of breathing. Eventually, there is resorption of alveolar oedema, regeneration of epithelial cells, proliferation and differentiation of type II alveolar cells and alveolar remodelling. Some show resolution and some progress to fibrosing alveolitis, which involves the deposition of collagen in alveolar, vascular and interstitial spaces.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 50
Incorrect
-
The anatomical dead space in a patient with low oxygen saturation, is 125 ml, with a tidal volume of 500 ml and pa(CO2) of 40 mm Hg. The dead space was determined by Fowler's method. If we assume that the patient's lungs are healthy, what will his mixed expired CO2 tension [pE(CO2)] be?
Your Answer:
Correct Answer: 30 mmHg
Explanation:According to Bohr’s equation, VD/VT = (pA(CO2) − pE(CO2))/pA(CO2), where pE(CO2) is mixed expired CO2 and pA(CO2) is alveolar CO2pressure. Normally, the pa(CO2) is virtually identical to pA(CO2). Thus, VD/VT = (pa(CO2)) − pE(CO2)/pa(CO2). By Fowler’s method, VD/VT= 0.25. In the given problem, (pa(CO2) − pE(CO2)/pa(CO2) = (40 − pE(CO2)/40 = 0.25. Thus, pE(CO2) = 30 mmHg. If there is a great perfusion/ventilation inequality, pE(CO2) could be significantly lower than 30 mm Hg, and the patient’s physiological dead space would exceed the anatomical dead space.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 51
Incorrect
-
A 55 year old lady underwent an uneventful appendicectomy. Two hours later, her arterial blood gas analysis on room revealed pH: 7.30, p(CO2): 53 mmHg and p(O2): 79 mmHg. What is the most likely cause of these findings?
Your Answer:
Correct Answer: Alveolar hypoventilation
Explanation:In the given problem, there is respiratory acidosis due to hypercapnia from a low respiratory rate and/or volume (hypoventilation). Causes of hypoventilation include conditions impairing the central nervous system (CNS) respiratory drive, impaired neuromuscular transmission and other causes of muscular weakness (drugs and sedatives), along with obstructive, restrictive and parenchymal pulmonary disorders. Hypoventilation leads to hypoxia and hypercapnia reduces the arterial pH. Severe acidosis leads to pulmonary arteriolar vasoconstriction, systemic vascular dilatation, reduced myocardial contractility, hyperkalaemia, hypotension and cardiac irritability resulting in arrhythmias. Raised carbon dioxide concentration also causes cerebral vasodilatation and raised intracranial pressure. Over time, buffering and renal compensation occurs. However, this might not be seen in acute scenarios where the rise in p(CO2) occurs rapidly.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 52
Incorrect
-
Which of the following structure contains the parasympathetic pre-ganglionic nucleus that innervates the iris sphincter muscle and the ciliary muscle?
Your Answer:
Correct Answer: Edinger–Westphal nucleus
Explanation:The Edinger–Westphal nucleus (accessory oculomotor nucleus) is the parasympathetic pre-ganglionic nucleus that innervates the iris sphincter muscle and the ciliary muscle.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 53
Incorrect
-
A surgical registrar performing an adrenalectomy procedure on the left suprarenal gland of a 25 - year old male patient, accidentally jabbed and injured a vital structure that lies anterior to the left suprarenal organ. Which of the following was the structure most likely injured?
Your Answer:
Correct Answer: Pancreas
Explanation:The adrenal (suprarenal) glands are organs of the endocrine system located on top of each of the kidneys. The left suprarenal gland, in question, is crescent in shape and slightly larger than the right suprarenal gland. It is posteriorly located to the lateral aspect of the head of the pancreas which is thus the most likely to be injured. The other organs like the duodenum, liver and the inferior vena cava are related to the right suprarenal gland. The spleen and the colon are not in close proximity with the left suprarenal gland and are not likely to be the organs injured.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 54
Incorrect
-
A middle aged man presented in OPD with a low grade fever and a persistent cough. His blood smear showed an increase in cells with large bi-lobed nuclei. Which of these cells represent the one seen on the smear?
Your Answer:
Correct Answer: Monocytes
Explanation:Monocytes are white cells that protect the body against harmful pathogens. They are mobile and are produced in the bone marrow, mature there and circulate in the blood for about 1-3 days, where they enter the tissues and transform into macrophages. They are characteristically identified by their large bi-lobed nuclei.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 55
Incorrect
-
Two boys were playing when one of them brought the forearm of the other behind his back. This resulted in a stretching of the lateral rotator of the arm. Which of the following muscles was most likely to have been involved?
Your Answer:
Correct Answer: Infraspinatus
Explanation:There are two lateral rotators of the arm, the infraspinatus and the teres minor muscles. The infraspinatus muscle receives nerve supply from C5 and C6 via the suprascapular nerve, whilst the teres minor is supplied by C5 via the axillary nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 56
Incorrect
-
A young 16 year old boy presented to the ENT clinic with a history of sore throat for the past 1 day. On examination there was a pharyngeal purulent discharge. Which of the following types of inflammation is seen in this boy?
Your Answer:
Correct Answer: Acute inflammation
Explanation:A 1 day history suggests the purulent discharge is due to acute inflammation. Acute inflammation has 3 features:
1) the affected area is occupied by a purulent discharge composed of proteins, fluids and cells from local blood vessels
2) the infective agent i.e. bacteria is present in the affected area
3) the damaged tissue can be liquified and the debris removed from the site.
If the inflammation lasts over weeks or months, then it is termed as chronic inflammation.
Granulomatous inflammation is characterised by the presence and formation of granulomas.
Exudate is not a feature of resolution or a complication of inflammation.
Abscess formation takes more than 1 day to form and is usually within a capsule/cavity.
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This question is part of the following fields:
- Inflammation & Immunology; Respiratory
- Pathology
-
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Question 57
Incorrect
-
A 29-year-old pregnant woman develops severe hypoxaemia with petechial rash and confusion following a fracture to her left femur. Which is the most probable cause of these symptoms in this patient?
Your Answer:
Correct Answer: Fat embolism
Explanation:Fat embolism is a life-threatening form of embolism in which the embolus consists of fatty material or bone marrow particles that are introduced into the systemic venous system. It may be caused by long-bone fractures, orthopaedic procedures, sickle cell crisis, parenteral lipid infusion, burns and acute pancreatitis. Patients with fat embolism usually present with symptoms that include skin, brain, and lung dysfunction.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 58
Incorrect
-
A new-born was found to have an undeveloped spiral septum in the heart. This is characteristic of which of the following?
Your Answer:
Correct Answer: Persistent truncus arteriosus
Explanation:Persistent truncus arteriosus is a congenital heart disease that occurs when the primitive truncus does not divide into the pulmonary artery and aorta, resulting in a single arterial trunk. The spiral septum is created by fusion of a truncal septum and the aorticopulmonary spiral septum. Incomplete development of these septa results in incomplete separation of the common tube of the truncus arteriosus and the aorticopulmonary trunk.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 59
Incorrect
-
What is the linea aspera:
Your Answer:
Correct Answer: Serves as an attachment for adductors of the thigh
Explanation:The linea aspera is a prominent longitudinal ridge or crest on the middle third of the femur. It has a medial and a lateral lip and a narrow, rough, intermediate line. The vastus medialis arises from the medial lip of the linea aspera and has superior and inferior prolongations. The vastus lateralis takes origin from the lateral lip . The adductor magnus is inserted into the linea aspera. Two muscles are attached between the vastus lateralis and the adductor magnus: the gluteus maximus is inserted above and the short head of the biceps femoris arises below. Four muscles are inserted between the adductor magnus and the vastus medialis: the iliacus and pectineus superiorly, and the adductor brevis and adductor longus inferiorly.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 60
Incorrect
-
A CT-scan report of a patient with gastric carcinoma shows that the lymph nodes around the coeliac trunk are enlarged. The coeliac trunk:
Your Answer:
Correct Answer: Gives rise to the splenic, left gastric and common hepatic arteries
Explanation:The coeliac trunk is a branch of the aorta arising just below the aortic hiatus of the diaphragm to pass nearly horizontally forward to divide into 3 large branches i.e. the left gastric, the hepatic and the splenic arteries. Occasionally it may give off one of the inferior phrenic arteries. It is covered by the lesser omentum and on the right side bordered by the right coeliac ganglion and the cardiac end of the stomach. Inferiorly it is bordered by the upper border of the pancreas and splenic vein. The embryonic midgut is supplied by the superior mesenteric artery.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 61
Incorrect
-
A patient sustained an iatrogenic injury to one of the structures passing through the deep inguinal ring. This was during an operation to repair an inguinal hernia. Which structure is most likely to be injured?
Your Answer:
Correct Answer: Round ligament of the uterus
Explanation:The deep inguinal ring transmits the spermatic cord in the man and the round ligament of the uterus in the female. It is bound below and medially by the inferior epigastric vessels (so these don’t go through it).
The ilioinguinal nerve, although it courses through the inguinal canal, does not pass through it.
The iliohypogastric nerves run between the internal oblique and transversus abdominis in the abdominal wall, piercing the internal oblique at the anterior superior iliac spine to travel just deep to the external oblique.
The inferior epigastric artery runs between the transversus abdominis and the peritoneum forming the lateral umbilical fold.
The medial umbilical ligament is the obliterated umbilical artery that it lies within the medial umbilical fold of peritoneum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 62
Incorrect
-
Electrophoresis is used to detect antibodies (immunoglobulins) in a blood sample from the umbilical artery of a new born. Which antibodies have the highest percentage in a new-born?
Your Answer:
Correct Answer: IgG
Explanation:IgG is a monomeric immunoglobulin. It is formed by two heavy chains and two light chains and has two binding sites. Its is the most abundant antibody that is equally distributed in the blood and the tissues. It is the only antibody that can pass through the placenta and thus the only antibody present in the baby after it is born. There are four subclasses: IgG1 (66%), IgG2 (23%), IgG3 (7%) and IgG4 (4%). IgG1, IgG3 and IgG4 cross the placenta easily
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This question is part of the following fields:
- General
- Physiology
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Question 63
Incorrect
-
A 5-year-old child is rushed to the emergency department because of fever, erythema and neck stiffness. The child is also hypotensive upon physical examination. Which is the most likely toxin responsible for this child's condition?
Your Answer:
Correct Answer: Endotoxin
Explanation:An endotoxin is part of the bacterial outer membrane, and it is not released until the bacterium is killed by the immune system. The body’s response to an endotoxin can involve severe inflammation. In general, the inflammation process is usually considered beneficial to the infected host, but if the reaction is severe enough, it can lead to sepsis.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 64
Incorrect
-
Dicloxacillin is an antibiotic; the subclass that dicloxacillin belongs to is:
Your Answer:
Correct Answer: Penicillin
Explanation:Dicloxacillin is a narrow-spectrum beta-lactam antibiotic. It is used to treat infections caused by susceptible Gram-positive bacteria and most effective against beta-lactamase-producing organisms such as Staphylococcus aureus. To decrease the development of resistance, dicloxacillin is recommended to treat infections that are suspected or proven to be caused by beta-lactamase-producing bacteria.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 65
Incorrect
-
Which muscle in the neck divides the neck into two large triangles?
Your Answer:
Correct Answer: Sternocleidomastoid
Explanation:The sternocleidomastoid muscle is an important landmark in the neck as it divides the neck into two; anterior and posterior triangles. These triangles help in the location of the structures of the neck including the carotid artery, head and neck lymph nodes, accessory nerve and the brachial plexus. It originates from the manubrium and medial portion of the clavicle and inserts on the mastoid process of the temporal bone, superior nuchal line. The sternocleidomastoid receives blood supply from the occipital artery and the superior thyroid artery. It is innervated by the accessory nerve (motor) and cervical plexus (sensory).
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 66
Incorrect
-
A 69 Year old lady presented to the emergency department following a massive myocardial infarction. She was found to be in hypotensive shock with focal neurological signs. Unfortunately the patient demised. What would be the expected findings on the brain biopsy?
Your Answer:
Correct Answer: Liquefactive necrosis
Explanation:Liquefactive necrosis is often associated with bacterial or fungal infections. However, hypoxic death of cells within the central nervous system can also result in liquefactive necrosis. The focal area is soft with a liquefied centre containing necrotic debris and dead white cells. This may later be enclosed by a cystic wall
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This question is part of the following fields:
- Cell Injury & Wound Healing; Neurology
- Pathology
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Question 67
Incorrect
-
A 49-year-old man, smoker, complains of a persisting and worsening cough over the past few months. He also has noted blood in his sputum. The patient has no other major health conditions. Which of the following investigative procedures should be done first?
Your Answer:
Correct Answer: Sputum cytology
Explanation:Sputum cytology is a diagnostic test used for the examination of sputum under a microscope to determine if abnormal cells are present. It may be used as the first diagnostic procedure to help detect a suspected lung cancer or certain non-cancerous lung conditions.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 68
Incorrect
-
A 30 year-old male patient sustained a sharp blow to the right side of the head, over the temporal region during a vehicular accident. This resulted to the rupture of the principal artery that supplies the meninges. Which artery is affected?
Your Answer:
Correct Answer: Middle meningeal artery
Explanation:The middle meningeal artery is typically the third branch of the first part of the maxillary artery, one of the two terminal branches of the external carotid artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater and the calvaria. The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. The anterior branch of the middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma .An injured middle meningeal artery is the most common cause of an epidural hematoma.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 69
Incorrect
-
A 17-year-old female was given an antibiotic for a urinary tract infection. After taking the medication the patient developed Steven-Johnson syndrome. Which particular antibiotic usually causes Steven-Johnson syndrome?
Your Answer:
Correct Answer: Sulphonamides
Explanation:Stevens–Johnson syndrome (SJS) is a type of severe skin reaction. The most common cause is certain medications such as lamotrigine, carbamazepine, allopurinol, sulphonamide antibiotics, and nevirapine.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 70
Incorrect
-
A medical student is told a substance is freely filtered but is not metabolised, secreted, or stored in the kidney. It has a plasma concentration of 1000 mg/l and its urine excretion rate is 25 mg/min, and the inulin clearance is 100 ml/min. What is the rate of tubular reabsorption of the substance?
Your Answer:
Correct Answer: 75 mg/min
Explanation:Reabsorption or tubular reabsorption is the process by which the nephron removes water and solutes from the tubular fluid (pre-urine) and returns them to the circulating blood. To calculate the reabsorption rate of substance Z we use the following equation: excretion = (filtration + secretion) – reabsorption. As this substance is freely filtered, its filtration rate is equal to that of inulin. So 25 = (100 + 0) – reabsorption. Reabsorption = 100 – 25 therefore reabsorption = 75 mg/min.
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This question is part of the following fields:
- Physiology
- Renal
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Question 71
Incorrect
-
The thyroid gland is a large ductless gland located in which part of the neck?
Your Answer:
Correct Answer: Visceral space
Explanation:The thyroid gland is an endocrine gland in the neck, consisting of two lobes connected by an isthmus. It is situated at the front and sides of the neck in the visceral space.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 72
Incorrect
-
A sexually active 21 year old man presents with the history of dysuria for the past 3 days. Urine culture confirmed Neisseria gonorrhoeae and smear showed abundant neutrophils. Which of the following mediators is responsible for causing diapedesis of the neutrophils to reach the site of infection?
Your Answer:
Correct Answer: Complement C5a
Explanation:C5a is part of the complement cascade and is released frim the complement C5. It acts as a chemotactic factor for neutrophils. Other chemotactic mediators are TNF, leukotrienes and bacterial products.
Bradykinin is associated with the production of pain and vasodilation.
Hageman factor is a clotting factor.
Histamine causes vasodilation.
C3B causes opsonisation.
IL-6 and IL-12 are inflammatory mediators causing B cell maturation and mediating inflammation and prostaglandins are involved with pain, increasing cell permeability and vasodilation.
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This question is part of the following fields:
- Inflammation & Immunology; Urology
- Pathology
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Question 73
Incorrect
-
A 40-year old lady presented to the hospital with fever and mental confusion for 1 week. On examination, she was found to have multiple petechiae all over her skin and mucosal surfaces. Blood investigations revealed low platelet count and raised urea and creatinine. A platelet transfusion was carried out, following which she succumbed to death. Autopsy revealed pink hyaline thrombi in myocardial arteries. What is the likely diagnosis?
Your Answer:
Correct Answer: Thrombotic thrombocytopenic purpura
Explanation:Hyaline thrombi are typically associated with thrombotic thrombocytopenic purpura (TTP), which is caused by non-immunological destruction of platelets. Platelet transfusion is contraindicated in TTP. Platelets and red blood cells also get damaged by loose strands of fibrin deposited in small vessels. Multiple organs start developing platelet-fibrin thrombi (bland thrombi with no vasculitis) typically at arteriocapillary junctions. This is known as ‘thrombotic microangiopathy’. Treatment consists of plasma exchange.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 74
Incorrect
-
Passing through the lesser sciatic foramen are the:
Your Answer:
Correct Answer: Pudendal nerve
Explanation:Structures that pass through the lesser sciatic foramen include:
– the pudendal nerve
– the nerve to obturator internus
– internal pudendal artery
– the tendon of obturator internus
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 75
Incorrect
-
During an operation to repair a hiatal hernia, the coeliac branch of the posterior vagal trunk is injured. This damage would affect muscular movements as well as some secretory activities of the gastrointestinal tract. Which gastrointestinal segment is LEAST likely to be affected?
Your Answer:
Correct Answer: Sigmoid colon
Explanation:The vagus nerve supplies the parasympathetic fibres to the abdominal structures that are receive arterial supply from the coeliac trunk or superior mesenteric artery i.e. up to the transverse colon. The end of the transverse colon and the gastrointestinal structures distal to this point receive parasympathetic innervation from the pelvic splanchnic nerves and blood from the inferior mesenteric artery(IMA). The ascending colon, caecum, jejunum and ileum would all, thus, be affected by this damage. Sigmoid colon would not be affected.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 76
Incorrect
-
In the glomerulus of the kidney, the mesangium is a structure associated with the capillaries. It has extraglomerular mesangial cells that:
Your Answer:
Correct Answer: Form the juxtaglomerular apparatus in combination with the macula densa and juxtaglomerular cells
Explanation:The mesangium is an inner layer of the glomerulus, within the basement membrane surrounding the glomerular capillaries. The mesangial cells are phagocytic and secrete the amorphous basement membrane-like material known as the mesangial matrix. They are typically separated from the lumen of the capillaries by endothelial cells. The other type of cells in the mesangium are the extraglomerular mesangial cells which form the juxtaglomerular apparatus in combination with two other types of cells: the macula densa of the distal convoluted tubule and juxtaglomerular cells of the afferent arteriole. This apparatus controls blood pressure through the renin–angiotensin–aldosterone system.
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This question is part of the following fields:
- Physiology
- Renal
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Question 77
Incorrect
-
Question 78
Incorrect
-
A 45-year-old woman was brought to the emergency department due to fever and chills. She has a history of recurrent UTI and complains of dysuria and urinary frequency. Urinary white blood cell count is >200 cell/high power field. If urine culture is performed, what is the most likely organism that will grow?
Your Answer:
Correct Answer: Escherichia coli
Explanation:The pathogen that most likely causes recurrent urinary tract infection in young women are E. coli, Enterococcus and Staphylococcus saprophyticus.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 79
Incorrect
-
Which of the cranial nerves is responsible for touch sensation on the skin over the maxilla region and the mandible?
Your Answer:
Correct Answer: Trigeminal
Explanation:The sensation of the face is provided by the trigeminal nerve which is cranial nerve V. It is also responsible for other motor functions such as biting and chewing. The trigeminal nerve has three branches; the ophthalmic nerve (V1), the maxillary nerve((V2) and the mandibular nerve (V3). These three branches exit the skull through separate foramina, namely; the superior orbital fissure, the foramen rotundum and the foramen ovale respectively. The mnemonic for this is ‘Standing room only’. The sensory fibres of the maxillary nerve are distributed to the lower eyelid and cheek, the nares and upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses, and parts of the meninges. The sensory fibres of the mandibular nerve are distributed to the lower lip, the lower teeth and gums, the floor of the mouth, the anterior two-thirds of the tongue, the chin and jaw (except the angle of the jaw, which is supplied by C2–C3), parts of the external ear, and parts of the meninges. The mandibular nerve carries touch/ position and pain/temperature sensation from the mouth. The sensory fibres of the ophthalmic nerve are distributed to the scalp and forehead, the upper eyelid, the conjunctiva and cornea of the eye, the nose (including the tip of the nose), the nasal mucosa, the frontal sinuses and parts of the meninges (the dura and blood vessels). The sensory fibres of the maxillary nerve are distributed to the lower eyelid and cheek, the nares and upper lip, the upper teeth and gums, the nasal mucosa, the palate and roof of the pharynx, the maxillary, ethmoid and sphenoid sinuses, and parts of the meninges.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 80
Incorrect
-
Which of these illnesses is most likely to precede Guillain-Barré syndrome?
Your Answer:
Correct Answer: Viral pneumonia
Explanation:Guillain–Barré syndrome (GBS) is characterized by a rapid-onset muscle weakness caused by the immune system damaging the peripheral nervous system. In about two-thirds of patients, the syndrome begins 5 days to 3 weeks after an infectious disease, surgery or vaccination. Infection is the trigger in over 50% of patients; common pathogens include Campylobacter jejuni, enteric viruses, herpesviruses (including cytomegalovirus and those causing infectious mononucleosis) and Mycoplasma species. The underlying mechanism involves an autoimmune disorder in which the body’s immune system mistakenly attacks the peripheral nerves and damages their myelin insulation, although the cause for this is still unknown.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 81
Incorrect
-
A patient is unable to move their mandible to the left. Which muscle is affected in this case?
Your Answer:
Correct Answer: Right lateral pterygoid muscle
Explanation:Patients with paralysis of the right pterygoid muscle are unable to move their mandible laterally to the left.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 82
Incorrect
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A 27-year-old HIV patient started on an antifungal agent. Which antifungal agent that inhibits the biosynthesis of fungal ergosterol was given to the patient?
Your Answer:
Correct Answer: Ketoconazole
Explanation:Ketoconazole is a synthetic imidazole antifungal drug used primarily to treat fungal infections. It inhibits the biosynthesis of ergosterol by blocking demethylation at the C14 site of the ergosterol precursor. Amphotericin B and Nystatin impair permeability of the cell membrane. Flucytosine interferes with DNA synthesis, while the target of griseofulvin is the microtubules
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 83
Incorrect
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What is the innervation of the laryngeal mucosa inferior to the true vocal cord?
Your Answer:
Correct Answer: Recurrent laryngeal nerve
Explanation:Motor innervation to all other muscles of the larynx and sensory innervation to the subglottis is by the recurrent laryngeal nerve.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 84
Incorrect
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A 45-year-old man with short bowel syndrome requires parenteral nutrition. The solution of choice for parenteral nutrition is:
Your Answer:
Correct Answer: Crystalline amino acids
Explanation:Total parenteral nutrition (TPN), is the practice of feeding a person intravenously, circumventing the gut. It is normally used in the following situations: surgery, when feeding by mouth is not possible, when a person’s digestive system cannot absorb nutrients due to chronic disease or if a person’s nutrient requirement cannot be met by enteral feeding and supplementation. A sterile bag of nutrient solution, between 500 ml and 4L, is provided. The pump infuses a small amount (0.1–10 ml/h) continuously to keep the vein open. The nutrient solution consists of water, glucose, salts, amino acids, vitamins and sometimes emulsified fats. Ideally each patient is assessed individually before commencing on parenteral nutrition, and a team consisting of doctors, nurses, clinical pharmacists and dietitians evaluate the patient’s individual data and decide what formula to use and at what rate.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 85
Incorrect
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A 36-year old gentleman with a history of cough for 4 weeks came to the hospital. Examination revealed multiple lymphadenopathy with splenomegaly. Investigations revealed haemoglobin 11 g/dl, haematocrit 32.4%, mean corpuscular volume (MCV) 93 fl, white blood cell count 63 × 109/l, and platelet count 39 × 109/l; along with characteristic Auer rods on peripheral blood smear. What is the likely diagnosis?
Your Answer:
Correct Answer: Acute myelogenous leukaemia (AML)
Explanation:AML, or acute myeloid leukaemia is the commonest acute leukaemia affecting adults. increasing in incidence with age. It is a malignancy of the myeloid line of white blood cells. It results in rapid proliferation of abnormal cells, which accumulate in the marrow. Interference with normal cell production leads to a drop in red blood cells, white blood cells and platelets. This causes symptoms such as tiredness, shortness of breath, tendency to bleed or bruise easily and recurrent infections. AML is known to progress quickly and can lead to death in weeks and months if not treated. Leukemic blasts of AML show presence of Auer rods. These are clumps of azurophilic granular material that form needles in the cytoplasm. Composed of fused lysosomes, these contain peroxidase, lysosomal enzymes and crystalline inclusions. Auer rods are classically present in myeloid blasts of M1, M2, M3 and M4 acute leukaemia. They also help to distinguish the preleukemia myelodysplastic syndromes.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 86
Incorrect
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A 35 year-old woman is undergoing thyroidectomy. The external laryngeal nerve may be injured whilst ligating this artery during the procedure due to its close relationship?
Your Answer:
Correct Answer: Superior thyroid artery
Explanation:The superior thyroid artery arises from the external carotid artery just below the level of the greater cornu of the hyoid bone and ends in the thyroid gland. This artery must be ligated at the thyroid when conducting a thyroidectomy. If the artery is severed, but not ligated, it will bleed profusely. In order to gain control of the bleeding, the surgeon may need to extend the original incision laterally to ligate the artery at its origin at the external carotid artery. The external laryngeal branch of the superior laryngeal nerve courses in close proximity to the superior thyroid artery, making it at risk for injury during surgery.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 87
Incorrect
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A 20-year old involved in a brawl was stabbed in the anterior chest in a structure that is in close proximity to where the first rib articulates with the sternum. What is the structure that was most likely injured?
Your Answer:
Correct Answer: Sternoclavicular joint
Explanation:The first rib articulates with the sternum right below the sternoclavicular joint.
The sternal angle articulates with the costal cartilage of the second rib.
The nipple is found between the fourth and the fifth ribs, in the fourth intercostal space.
The xiphoid process is located right below the point of articulation of the costal cartilage of rib 7 with the sternum.
The root of the lung is the part of the lung where neurovascular structures enter and leave the lung.
Acromioclavicular joint is the point of articulation between the acromion process and the clavicle, near the shoulder.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 88
Incorrect
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A 68-year-old woman complains of headaches, dizziness, and memory loss. About a month ago, she fell from a staircase but only suffered mild head trauma. What is the most likely diagnosis in this case?
Your Answer:
Correct Answer: Chronic subdural haematoma
Explanation:A quarter to a half of patients with chronic subdural haematoma have no identifiable history of head trauma. If a patient does have a history of head trauma, it usually is mild. The average time between head trauma and chronic subdural haematoma diagnosis is 4–5 weeks. Symptoms include decreased level of consciousness, balance problems, cognitive dysfunction and memory loss, motor deficit (e.g. hemiparesis), headache or aphasia. Some patients present acutely. They usually result from tears in bridging veins which cross the subdural space, and may cause an increase in intracranial pressure (ICP).
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This question is part of the following fields:
- Neurology
- Pathology
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Question 89
Incorrect
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A 29-year-old pregnant woman suffering from hyperemesis gravidarum is prescribed metoclopramide. What is the mechanism of action of metoclopramide?
Your Answer:
Correct Answer: Dopamine antagonist
Explanation:Metoclopramide is a potent dopamine-receptor antagonist with anti-emetic and prokinetic properties. It is therefore commonly used to treat nausea and vomiting, and to facilitate gastric emptying in patients with gastric stasis. The anti-emetic action of metoclopramide is due to its antagonist activity at D2 receptors in the chemoreceptor trigger zone (CTZ) in the central nervous system. Common adverse drug reactions associated with metoclopramide include restlessness (akathisia), and focal dystonia.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 90
Incorrect
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Renal function is an indication of the state of the kidney, measured by glomerular filtration rate (GFR). In a healthy person, GFR would be greatly increased by:
Your Answer:
Correct Answer: Substantial increases in renal blood flow
Explanation:An increase in the rate of renal blood flow (RBF) greatly increases the glomerular filtration rate (GFR). The more plasma available (from increased RBF), the more filtrate is formed. Glomerular filtration rate (GFR) is the volume of fluid filtered from the renal (kidney) glomerular capillaries into the Bowman’s capsule per unit time. Central to the physiologic maintenance of GFR is the differential basal tone of the afferent and efferent arterioles.
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This question is part of the following fields:
- Physiology
- Renal
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Question 91
Incorrect
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A biopsy is performed on a 67-year-old-man with testicular seminoma; it reveals that the tumour affects the tunica vaginalis. The tumour stage in this case is:
Your Answer:
Correct Answer: T2
Explanation:The primary tumour staging for testicular seminoma is as follows, according to AJCC guidelines:
Tis: intratubular germ cell neoplasia (carcinoma in situ)
T1: tumour limited to testis/epididymis without vascular or lymphatic invasion; the tumour can invade into the tunica albuginea but not the tunica vaginalis
T2: tumour limited to testis/epididymis with vascular or lymphatic invasion or tumour extending through the tunica albuginea with involvement of the tunica vaginalis
T3: tumour invading the spermatic cord, with or without vascular/lymphatic invasion
T4: tumour invading the scrotum, with or without vascular/lymphatic invasion.
According to these guidelines, the tumour in this case has a T2 stage.
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This question is part of the following fields:
- Pathology
- Urology
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Question 92
Incorrect
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Which of the following morphological characteristic is a salient feature of a pure apoptotic cell?
Your Answer:
Correct Answer: Chromatin condensation
Explanation:Apoptosis is the programmed death of cells which occurs as a normal and controlled part of an organism’s growth or development. The changes which occur in this process include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, chromosomal DNA fragmentation, and global mRNA decay. The cell membrane however remains intact and the dead cells are phagocytosed prior to any content leakage and thus inflammatory response.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 93
Incorrect
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Anthrax is an infection caused by the bacterium Bacillus anthracis. Anthrax spores have been used as a biological warfare weapon. What is the drug of choice in treating anthrax infection?
Your Answer:
Correct Answer: Ciprofloxacin
Explanation:Early antibiotic treatment of anthrax is essential. A delay may significantly lessen the chances for survival of the patient. Treatment for anthrax infection include large doses of intravenous and oral antibiotics, such as fluoroquinolones (ciprofloxacin), doxycycline, erythromycin, vancomycin, or penicillin.
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This question is part of the following fields:
- Microbiology
- Pathology
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Question 94
Incorrect
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When a patient is standing erect, pleural fluid would tend to accumulate in which part of the pleural space?
Your Answer:
Correct Answer: Costodiaphragmatic recess
Explanation:The costo-diaphragmatic recess is the lowest extent of the pleural cavity or sac. Any fluid in the pleura will by gravity accumulate here when a patient is standing erect.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 95
Incorrect
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A 15-day old baby was brought to the emergency department with constipation for 4 days. On examination, the abdomen of the baby was found to be distended and tender all over. No bowel sounds were heard. A sigmoid colon biopsy was carried out, which showed absent ganglion cells. What is the diagnosis?
Your Answer:
Correct Answer: Hirschsprung’s disease
Explanation:Hirschsprung’s disease is characterized by congenital absence of the autonomic plexus (Meissner’s and Auerbach’s plexus) in the intestinal wall. Usually limited to the distal colon, it can occasionally involve the entire colon or even the small bowel. There is abnormal or absent peristalsis in the affected segment, resulting in continuous spasm of smooth muscle and partial/complete obstruction. This causes accumulation of intestinal contents and dilatation of proximal segment. Skip lesions are highly uncommon. This disease is seen early in life with 15% patients presenting in first month, 60% by 1 year of age and 85% by the age of 4 years. Symptoms include severe and complete constipation, abdominal distension and vomiting. Patients with involvement of ultra-short segments might have mild constipation with intervening diarrhoea. In older children, symptoms include failure to thrive, anorexia, and lack of an urge to defecate. On examination, an empty rectum is revealed with stool palpable high up in the colon. If not diagnosed in time, it can lead to Hirschsprung’s enterocolitis (toxic megacolon), which can be fulminant and lead to death. Diagnosis involves a barium enema or a rectal suction biopsy. Barium enema shows a transition in diameter between the dilated, normal colon proximal to the narrowed, affected distal segment. It is to be noted that barium enema should be done without prior preparation, which can dilate the abnormal segment, leading to a false-negative result. A 24-hour post-evacuation film can be obtained in the neonatal period – if the colon is still filled with barium, there is a high likelihood of Hirschsprung’s disease. Full-thickness rectal biopsy is diagnostic by showing the absence of ganglion cells. Acetylcholinesterase staining can be done to highlight the enlarged nerve trunks. Abnormal innervation can also be demonstrated by rectal manometry.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 96
Incorrect
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The stomach is an organ that is divided into several important anatomical parts. These parts of the stomach have varied arterial blood supply that ensure that the whole organ receive oxygenated blood. Which of the following arteries if ligated, will not render any portion of the stomach ischaemic?
Your Answer:
Correct Answer: Superior mesenteric
Explanation:The blood supply to the stomach is through the following arteries:
– The superior mesenteric artery supplies blood to the lower part of the duodenum, pancreas and two-thirds of the transverse colon. Thus ligation of the superior mesenteric artery would not affect the stomach.
– The right and the left gastroepiploic arteries supply the greater curvature of the stomach – along its edges.
– The short gastric artery supplies blood to the upper portion of the of the greater curvature and the fundus of the stomach.
– The gastroduodenal artery supplies blood to the distal part of the stomach (the pyloric sphincter) and the proximal end of the duodenum.
– The left gastroepiploic and the short gastric are branches of the splenic artery and therefore ligation of the splenic artery would directly affect the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 97
Incorrect
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An explorative laparotomy is done on a 23 year old following a gunshot abdominal injury through the right iliac fossa. It is found that the ileocolic artery is severed and the bullet had perforated the caecum. From which branch does the ileocolic artery originate?
Your Answer:
Correct Answer: Superior mesenteric artery
Explanation:Ileocolic artery branches off from the superior mesenteric artery. It then divides to give a superior and inferior branch.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 98
Incorrect
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A 45 year old female had a stroke and was diagnosed with a homonymous hemianopsia. Which of the following structures was likely affected?
Your Answer:
Correct Answer: Optic radiation
Explanation:Hemianopia or hemianopsia, is the loss of vision of half of the eye or loss of half the visual field. Homonymous hemianopia is the loss of vision or blindness on half of the same side of both eyes (visual field) – either both lefts of the eyes or both rights of the eyes. This condition is mainly caused by cerebrovascular accidents like a stroke that affects the optic radiation.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 99
Incorrect
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Due to a plantarflexion–inversion ankle sprain, which is the first ligament to rupture?
Your Answer:
Correct Answer: Anterior talofibular ligament
Explanation:The anterior talofibular ligament passes from the anterior margin of the fibular malleolus. It is the most commonly injured ligament, as part of the lateral ligament of the ankle.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 100
Incorrect
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The superior rectal artery is a continuation of the:
Your Answer:
Correct Answer: Inferior mesenteric artery
Explanation:The superior rectal artery or superior haemorrhoidal artery is the continuation of the inferior mesenteric artery. It descends into the pelvis between the layers of the mesentery of the sigmoid colon, crossing the left common iliac artery and vein.
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This question is part of the following fields:
- Abdomen
- Anatomy
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