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Question 1
Correct
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Which of the following is likely to result in hematocolpos in a 12-year old girl?
Your Answer: Imperforate hymen
Explanation:Hematocolpos means accumulation of blood in vagina and hematometra is accumulation of blood in the uterus. These are most likely seen with an imperforate hymen; which is seen I 1 in 2000 females. If spontaneous resolution does not occur, treatment involves making a hole in the hymen to allow discharge of menstrual blood.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 2
Incorrect
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Whipple's procedure involves mobilizing the head of the pancreas. As the surgeon does this, he must be careful to avoid injury to a key structure that is found lying behind the head of the pancreas. Which vital structure is this?
Your Answer: Superior mesenteric vein
Correct Answer: Common bile duct
Explanation:The posterior relations of the head of the pancreas include: the inferior vena cava, the common bile duct, the renal veins, the right crus of the diaphragm and the aorta.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 3
Correct
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Which of the following has the highest content of triglycerides?
Your Answer: Chylomicron
Explanation:Created by the small intestinal cells, chylomicrons are large lipoprotein molecules which transport lipids to the liver, adipose, cardiac and skeletal tissue. Chylomicrons are mainly composed of triglycerides (,85%) along with some cholesterol and cholesteryl esters. Apo B-48 is the main apolipoprotein content.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 4
Correct
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A 60 year-old patient being treated for hypertension presents to the ED with swelling of the left upper limb due to poor venous return. On examination, it is found that an aneurysm of the ascending aorta is impinging on a large vein lying immediately anterosuperior to it. Which vein is it likely to be?
Your Answer: Left brachiocephalic
Explanation:Among the veins listed, only the left brachiocephalic vein is anterosuperior to the ascending aorta. The right brachiocephalic vein being on the right side would not be affected by the aortic aneurysm.
The azygos vein lies deep in the chest on the right side.
The internal thoracic vein lies interior to the anterior wall of the chest.
The left superior intercostal vein is close to the aortic arch, crossing it laterally. This vein drains the 2nd to 4th interspaces on the left side.
The Right internal jugular vein joins the right brachiocephalic vein which would not be affected by the aneurysm.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 5
Incorrect
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A 56 year old gentleman, who is a chronic smoker presents to the clinic with dyspnoea. His Chest X-ray shows intercostal space widening with increased blackening bilaterally. What is the most likely finding on his pulmonary function test?
Your Answer: Decreased total lung capacity
Correct Answer: Increased total lung capacity
Explanation:In patients suspected of having chronic obstructive pulmonary disease, pulmonary function testing (PFT) is useful to confirm airway obstruction, to quantify its severity and reversibility, for following disease progression and monitoring response to treatment. These tests include:
FEV1 – volume of air forcefully expired during the first second after a full breath
Forced vital capacity (FVC) – total volume of air expired with maximal force and flow-volume loops. The hallmark of airway obstruction is reduction of FEV1, FVC and the ratio of FEV1/FVC, with a concave pattern in expiratory tracing on the flow-volume loop. FEV1 and forced vital capacity (FVC) are easily measured with office spirometry and are useful to assess the severity of disease. Other parameters include increased total lung capacity, functional residual capacity and residual volume, which can help distinguish chronic obstructive pulmonary disease (COPD) from restrictive pulmonary disease where these values are lower than normal. Along with these, other tests are decreased vital capacity; and decreased diffusing capacity for carbon monoxide (DLCO). DLCO is non-specific and can be low in other disorders that affect the pulmonary vascular bed, such as interstitial lung disease. DLCO is however useful to distinguish COPD from asthma, in which DLCO is normal or elevated.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 6
Correct
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A machine worker fractured the medial epicondyle of his right humerus resulting in damage to an artery running with the ulnar nerve posterior to the medial epicondyle. The artery injured is the?
Your Answer: Superior ulnar collateral
Explanation:The superior ulnar collateral artery runs posterior to the medial epicondyle of the humerus, accompanied by the ulnar nerve. This artery arises from the brachial artery near the middle of the arm and ends under the flexor carpi ulnaris muscle by anastomosing with two arteries: the posterior ulnar recurrent and inferior ulnar collateral.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 7
Correct
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Which statement is correct regarding coagulation?
Your Answer: Thrombin converts fibrinogen to fibrin
Explanation:Coagulation of blood is a complex process and an important part of haemostasis. There are two main pathways related to coagulation: the contact activation pathway/intrinsic pathway and tissue factor/extrinsic pathway. The extrinsic pathway is activated by external trauma that causes blood to escape from the vascular system. This pathway is quicker than the intrinsic pathway and involves factor VII. The intrinsic pathway is activated by trauma inside the vascular system, and initiated by platelets, exposed endothelium, chemicals, or collagen. This pathway is slower than the extrinsic pathway, but more important. It involves factors XII, XI, IX, VIII. Both pathways meet to finish the formation of a clot in what is known as the common pathway. The common pathway involves factors I, II, V, and X. They converge on the common pathway in which activation of prothrombin to thrombin leads to conversion of fibrinogen to fibrin and clot formation.
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This question is part of the following fields:
- General
- Physiology
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Question 8
Incorrect
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The accumulation of eosinophils within tissues is mostly regulated by which of the following cytokines?
Your Answer: Interleukin 3
Correct Answer: Interleukin-5
Explanation:IL-5 is produced by TH2 helper cells and by mast cells. They stimulate increased secretion of immunoglobulins and stimulate B cell growth. They are the major regulators in eosinophil activation and control. They are also released from eosinophils and mast cells in asthmatic patients and are associate with a many other allergic conditions.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 9
Correct
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Which organs would cause pain in a patient who complains of dull pain in her pelvis, along the midline starting from the pubic bone in the front to the sacrum at the back?
Your Answer: Urinary bladder, uterus/cervix/vagina, rectum
Explanation:The pain could have been caused by the urinary bladder, uterus/cervix/vagina or rectum as it involves the pelvic viscera.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 10
Incorrect
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A 35-year-old woman is in a comatose state following a traumatic head injury, and is receiving intravenous (IV) antibiotics and IV fluids containing saline and 5% dextrose. A serum biochemistry analysis is performed five days later which shows a low serum potassium level. This is most likely to be due to:
Your Answer: Surgical injury
Correct Answer: Nothing per oral regimen
Explanation:In this patient the cause for hypokalaemia is insufficient consumption of potassium as she is nil-per mouth with no intravenous supplementation. Parenteral nutrition has been used for comatose patients, although enteral feeding is usually preferable, and less prone to complications.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 11
Correct
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A 70-year old man who is suspected to have a perforated colonic diverticulum is explored in theatre through a midline incision. This incision will be through the:
Your Answer: Linea alba
Explanation:The linea alba is the point where this incision was made. It is a tendinous raphe in the midline of the abdomen extending between the xiphoid process and the symphysis pubis. It is placed between the medial borders of the recti and is formed by the blending of the aponeuroses of the external and internal obliques and transversi.
The linea aspera is a vertical ridge on the posterior surface of the femur.
The arcuate line is the inferior border of the posterior rectus sheath behind the rectus abdominis muscle.
The semilunar line is the lateral margin of the rectus abdominis.
The iliopectineal line is a line on the pelvic bones formed by the arcuate line of the ilium and the pectineal line of the pubis.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 12
Correct
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The inferior palpebral nerve ascends behind the orbicularis oculi. What is the terminal branch of the inferior palpebral nerve?
Your Answer: Infraorbital nerve
Explanation:The inferior palpebral nerve is a branch of the maxillary nerve. It supplies the skin and conjunctiva of the lower eyelid.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 13
Incorrect
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During an anatomy revision session, medical students are told that the posterior wall of the rectus sheath ends in a thin curved margin whose concavity is directed downwards. What is the name of this inferior border of the rectus sheath?
Your Answer: Linea alba
Correct Answer: Arcuate line
Explanation:The rectus sheath is a tendinous sheath that encloses the rectus abdominis muscle. It covers the entire anterior surface however on the posterior surface of the muscle the sheath is incomplete ending inferiorly at the arcuate line. Below the arcuate line, the rectus abdominis is covered by the transversalis fascia. The linea alba is a band of aponeurosis on the midline of the anterior abdominal wall, which extends from the xiphoid process to the pubic symphysis. It is formed by the combined abdominal muscle aponeuroses. This is a useful site for midline incision during abdominal surgery because it does not carry many blood vessels. All of the other answer choices are related to the inguinal canal.
The falx inguinalis (sometimes called the inguinal falx or conjoint tendon), is the inferomedial attachment of the transversus abdominis with some fibres of the internal abdominal oblique – it contributes to the posterior wall of the inguinal canal.
The inguinal ligament is the ligament that connects the anterior superior iliac spine with the pubic tubercle – it makes the floor of the inguinal canal.
The internal (deep) inguinal ring is the entrance to the inguinal canal, where the transversalis fascia pouches out and creates an opening through which structures can leave the abdominal cavity.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 14
Incorrect
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A 60 year old female patient who has suffered an embolic stroke that affected her middle cerebral artery as revealed by a CT scan is likely to exhibit which of the following neurologic conditions?
Your Answer: Bitemporal hemianopia
Correct Answer: Contralateral hemiplegia
Explanation:The middle cerebral artery is a major artery that supplies blood to the cerebrum. It continues from the internal carotid artery up into the lateral sulcus. The middle cerebral artery mainly supplies the lateral aspect of the cerebral cortex, anterior aspect of the temporal lobes and the insular cortices.
Functional areas supplied by this vein are as follows:
The motor and pre-motor areas
The somato-sensory
Auditory areas
Motor speech
Sensory speech
Pre-frontal area
Occlusion of the middle cerebral artery results in:
i) A severe contralateral hemiplegia, most marked in the upper extremity and face
ii) A contralateral sensory impairment worse in the upper part of the body.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 15
Correct
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An amateur body-builder complains of increasing pain in his right shoulder after a few days of intense training. A surgeon aspirates clear fluid from his subdeltoid region. What's the most likely diagnosis?
Your Answer: Bursitis
Explanation:Bursae are potential cavities that contain synovial fluid, found in areas where friction occurs. Their function is to minimise friction and facilitate movement. Bursitis is the inflammation of one or more bursae, and they can occur in the shoulder, elbow, knee, ischium, amongst other joints. Acute bursitis can appear after strenuous exercise or activity, and chronic bursitis can develop following previous bursitis or trauma. Acute bursitis causes pain, tenderness, and swelling.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 16
Correct
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Cervical intraepithelial neoplasia on Pap smear of a 34-year old lady is most likely associated with which of the following?
Your Answer: Human papillomavirus infection
Explanation:CIN (Cervical intraepithelial neoplasia) is considered a precursor of cervical cancer and is likely caused due to infection with human papillomavirus (HPV) types 16, 18, 31, 33, 35 or 39. The risk factors for cervical cancer include multiple sex partners, young age at the time of first intercourse, intercourse with men whose previous partners had cervical cancer. Also, smoking and immunodeficient states are considered contributory. CIN is graded as mild (grade I), moderate (grade II) and severe dysplasia or carcinoma in situ (grade III). CIN III rarely regresses spontaneously and can lead to invasive carcinoma by invading the basement membrane. Squamous cell carcinomas are the commonest cervical cancer seen in 80-85% of all cases. Others are commonly adenocarcinomas. Cervical cancer can spread by direct extension, lymphatic spread to pelvic and para-aortic nodes or by hematogenous route.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 17
Incorrect
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From which branchial (pharyngeal) pouch does the inferior parathyroid gland arise?
Your Answer: 2nd
Correct Answer: 3rd
Explanation:The following structures arise from each branchial pouch:
1st pouch – eustachian tube, middle ear, mastoid, and inner layer of the tympanic membrane
2nd pouch – middle ear, palatine tonsils
3rd pouch – inferior parathyroid glands, thymus
4th pouch – superior parathyroid glands, ultimobranchial body which forms the parafollicular C-cells of the thyroid gland, musculature and cartilage of larynx (along with the sixth pharyngeal pouch)
5th pouch – rudimentary structure
6th pouch – along with the fourth pouch, contributes to the formation of the musculature and cartilage of the larynx.
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This question is part of the following fields:
- Anatomy
- Endocrine; Embryology
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Question 18
Correct
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A 55-years-old man presented to the emergency department complaining of a squeezing sensation in his chest that has spread to his neck with associated worsening shortness of breath. Which of these laboratory tests would you ask for in this patient:
Your Answer: Creatine kinase-MB
Explanation:Creatine kinase-MB is a test that usually is ordered when the patient has chest pain as a cardiac marker. When a heart attack is suspected and a troponin test (which is more specific for heart damage), is not available CK-MB is ordered. There are 3 forms of CK: CK-MM, CK-BB and CK-MB. CK-MB is commonly found in heart tissue, therefore injured heart muscle cells release CK-MB into the blood. Elevated CK-MB levels indicate that it is probable that a person has recently had a heart attack.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 19
Correct
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During uterogrowth, the second pharyngeal arch gives rise to which structures?
Your Answer: Stylohyoid muscle
Explanation:The second pharyngeal arch or hyoid arch, is the second of six pharyngeal arches that develops in fetal life during the fourth week of development and assists in forming the side and front of the neck. Derivatives:
Skeletal – From the cartilage of the second arch arises:
Stapes,
Temporal styloid process,
Stylohyoid ligament, and
Lesser cornu of the hyoid bone.
Muscles:
Muscles of face
Occipitofrontalis muscle
Platysma
Stylohyoid muscle
Posterior belly of Digastric
Stapedius muscle
Auricular muscles
Nerve supply: Facial nerve
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 20
Correct
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A 34-year-old man is receiving chemotherapy for non-Hodgkin's lymphoma. Which of the following chemotherapy regimens would be used in this case?
Your Answer: CHOP
Explanation:CHOP is the acronym for a chemotherapy regimen used in the treatment of non-Hodgkin’s lymphoma, comprising cyclophosphamide, hydroxyrubicin (adriamycin), vincristine and prednisone. This regimen can also be combined with the monoclonal antibody rituximab if the lymphoma is of B cell origin; this combination is called R-CHOP.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 21
Correct
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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: 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 22
Incorrect
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Normally, the O2 transfer in the lungs from alveolar to capillary is perfusion-limited. In which of the following situations does it become a diffusion-limited process?
Your Answer: Increased ventilatory rate
Correct Answer: Pulmonary oedema
Explanation:Normally, the transfer of oxygen from air spaces to blood takes place across the alveolar-capillary membrane by simple diffusion and depends entirely on the amount of blood flow (perfusion-limited process). Diseases that affect this diffusion will transform the normal process to a diffusion limited process. Thus, the diseases which cause a thickened barrier (such as pulmonary oedema due to increased extravascular lung water or asbestosis) will limit the diffusion of oxygen. Chronic obstructive lung diseases will have little effect on diffusion. Inhaling hyperbaric gas mixtures might overcome the diffusion limitation in patients with mild asbestosis or interstitial oedema, by increasing the driving force. Strenuous (not mild) exercise might also favour diffusion limitation and decrease passage time. Increasing the rate of ventilation will not have this affect but will only maintain a high oxygen gradient from air to blood.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 23
Correct
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A 50 year old man was admitted to the surgical ICU following a hemicolectomy for carcinoma of the caecum. A full blood count revealed: haematocrit = 30%, erythrocytes = 4 × 106/μ, haemoglobin level = 8 g/dl. To determine the likely cause of his anaemia, red blood cell indices were calculated. Which RBC indices are correct?
Your Answer: MCHC = haemoglobin concentration/haematocrit
Explanation:Mean corpuscular haemoglobin concentration (MCHC) is calculated simply by dividing the haemoglobin concentration (8 g/dl) by the haematocrit (0.3). The normal range is 31–36 g/dl. This patient has a hypochromic anaemia (MCHC = 8/0.3 = 26.7 g/dl). Dividing the haemoglobin concentration × 10 by erythrocyte number yields mean corpuscular haemoglobin (MCH). Normal range is 25.4–34.6 pg/cell and this patient has a significantly reduced cellular haemoglobin content (MCH = 8 × 10/4 = 20 pg/cell). Mean corpuscular volume (MCV) is calculated by dividing haematocrit × 1000 by erythrocyte number (4 × 106/μl). Normal range is 80–100 fl and this patient has a microcytic anaemia (MCV = 0.3 × 1000/4 = 75 fl). Microcytic, hypochromic anaemia is characteristic for iron-deficiency.
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This question is part of the following fields:
- General
- Physiology
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Question 24
Correct
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Ventricular filling follows a delay caused by?
Your Answer: AV node
Explanation:The AV node is a conducting tissue found between the atria and the ventricles of the heart. It conducts electrical signal from the atria to the ventricles and acts a delaying mechanism preventing the atria and the ventricles from contracting at the same time. This decremental conduction prevents premature ventricular contraction in cases such as atrial fibrillation. A delay in the AV node is the reason for the PR segment seen on the ECG. In certain types of supraventricular tachycardia, a person could have two AV nodes; this will cause a loop in electrical current and uncontrollably rapid heart beat. When this electricity catches up with itself, it will dissipate and return to a normal heart rate.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 25
Correct
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What is the primary function of the Kupffer cells found in the liver?
Your Answer: Recycling of old red blood cells
Explanation:Kupffer cells found in the liver are part of the monocyte-reticular system. They are specialised macrophages and primarily function to recycle old and damaged RBCs. The RBCs are phagocytosed and the haemoglobin is broken down into haem and globin. The haem is further broken down into iron that is recycled and bilirubin that is conjugated with glucuronic acid and excreted in the bile.
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This question is part of the following fields:
- Inflammation & Immunology; Hepatobiliary
- Pathology
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Question 26
Correct
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Following a posterolateral thoracotomy, a surgeon may wish to infiltrate local anaesthetic above and below the incision to block the nerves supplying the thoracic wall. This wall is innervated by?
Your Answer: Intercostal nerves
Explanation:Intercostal nerves are the ventral primary rami of spinal nerves T1–T11. They give branches which supply the thoracic wall.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 27
Incorrect
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During a case presentation, a 26 year old is said to have fractured his pelvis and shattered his coccyx following a motorbike accident. It is mentioned that he is likely to have lacerated his middle sacral artery from this kind of injury. Where does the middle sacral artery branch from?
Your Answer: External iliac artery
Correct Answer: Abdominal aorta
Explanation:The middle sacral artery arises from behind the aorta a little above the point of its bifurcation to descend down in front of L4,5, the sacrum and coccyx.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 28
Correct
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A 65-year old patient with altered bowl movement experienced the worsening of shortness of breath and exertional chest pains over the course of 8 weeks. Examination shows pallor and jugular venous distension. Furthermore, a test of the stool for occult blood is positive. Laboratory studies show:
Haemoglobin 7.4 g/dl
Mean corpuscular volume 70 fl Leukocyte count 5400/mm3
Platelet count 580 000/mm3 Erythrocyte sedimentation 33 mm/h
A blood smear shows hypochromic, microcytic RBCs with moderate poikilocytosis. Which of the following is the most likely diagnosis?Your Answer: Iron deficiency anaemia
Explanation:Iron deficiency anaemia is the most common type of anaemia. It can occur due to deficiency of iron due to decreased intake or due to faulty absorption. An MCV less than 80 will indicated iron deficiency anaemia. On the smear the RBC will be microcytic hypochromic and will also show piokilocytosis. iron profiles tests are important to make a diagnosis. Clinically the patient will be pale and lethargic.
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This question is part of the following fields:
- General
- Physiology
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Question 29
Incorrect
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During work up for a 29 year-old lady who complained of chest pain, a computed tomography showed a large mass in the posterior mediastinum. Which among the following structures could be involved?
Your Answer: Ascending aorta
Correct Answer: Lymph nodes
Explanation:Boundaries of the posterior mediastinum include:
Superior: a plane through the sternal angle and T4/5
Inferior: the diaphragm
Anterior: the middle mediastinal structures
Posterior the spinal cord.
Structures in the posterior mediastinum include the descending thoracic aorta, the azygos system, oesophagus, thoracic duct and lymph nodes. The great vessels and structures at the root of the lung are part of the middle mediastinum. In this case, the lymph nodes is the correct answer.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 30
Incorrect
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A 46-year old lady presents with chief complaints of a large mass in the left breast. Histopathology of the mass revealed a stromal component with an epithelial component. What is the likely lesion?
Your Answer: Medullary carcinoma of breast
Correct Answer: Phyllodes tumour
Explanation:Phyllodes tumours are large, quickly growing tumours which arise from the periductal stroma of the breast. These are fibroepithelial tumours and account for less than 1% of breast cancers. These tumours can be benign, borderline or malignant based on the histology. The tumour usually affects adult women, mostly between the age of 40 to 50 years. It can be confused with fibroadenoma, which however affects much younger patients.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 31
Correct
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Linezolid is an antibiotic used for the treatment of infections caused by bacteria that are resistant to other antibiotics. Which of the following organisms is most likely to be effectively treated by linezolid?
Your Answer: Methicillin-resistant Staphylococcus aureus
Explanation:Linezolid is a synthetic antibiotic used for the treatment of infections caused by multiresistant bacteria, including streptococci and methicillin-resistant Staphylococcus aureus (MRSA). Linezolid is effective against Gram-positive pathogens, notably Enterococcus faecium, S. aureus, Streptococcus agalactiae, Streptococcus pneumoniae and Streptococcus pyogenes. It has almost no effect on Gram-negative bacteria and is only bacteriostatic against most enterococci.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 32
Correct
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Etoposide is a chemotherapeutic agent used in the treatment of different types of cancer. Which of the following is the correct indication for this drug?
Your Answer: Lung cancer
Explanation:Etoposide phosphate is an inhibitor of the enzyme topoisomerase II. It is used as a form of chemotherapy for malignancies such as lung cancer, testicular cancer, lymphoma, non-lymphocytic leukaemia and glioblastoma multiforme. Side effects are very common and can include low blood cell counts, vomiting, loss of appetite, diarrhoea, hair loss, and fever.
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This question is part of the following fields:
- Pathology
- Pharmacology
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Question 33
Correct
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The following joint has an anastomotic circulation that is provided by branches of the brachial artery:
Your Answer: Elbow joint
Explanation:The arterial anastomoses of the elbow joint is contributed by branches of the brachial artery and the Profunda brachii artery. The brachial artery gives off the superior ulnar collateral artery and the inferior collateral artery. On the other hand, the Profunda brachii gives off the radial and medial recurrent arteries.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 34
Correct
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A medical student is asked to calculate the net pressure difference in a capillary wall, considering: Interstitial fluid hydrostatic pressure = –3 mmHg, Plasma colloid osmotic pressure = 28 mmHg, Capillary hydrostatic pressure = 17 mmHg, Interstitial fluid colloid osmotic pressure = 8 mmHg, and Filtration coefficient = 1. Which is the correct answer?
Your Answer: 0 mmHg
Explanation:The rate of filtration at any point along a capillary depends on a balance of forces sometimes called Starling’s forces after the physiologist who first described their operation in detail. The Starling principle of fluid exchange is key to understanding how plasma fluid (solvent) within the bloodstream (intravascular fluid) moves to the space outside the bloodstream (extravascular space). Fluid movement = k[(pc– pi)–(Πc– Πi)] where k = capillary filtration coefficient, pc = capillary hydrostatic pressure, pi= interstitial hydrostatic pressure, Πc = capillary colloid osmotic pressure, Πi = interstitial colloid osmotic pressure. Therefore: 1 × [capillary hydrostatic pressure (17) – interstitial fluid hydrostatic pressure (–3)] – [plasma colloid osmotic pressure (28) – interstitial fluid colloid osmotic pressure (8)] = 0 mmHg
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 35
Correct
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An old man presented with atrophy of the thenar eminence despite the sensation over it still being intact. What is the injured nerve in this case?
Your Answer: Median nerve
Explanation:Atrophy of the thenar muscles means injury to the motor supply of these muscles. The nerve that sends innervation to it is the median nerve. But the median nerve does not provide sensory innervation to the overlying skin so sensation is spared.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 36
Correct
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A glycogen storage disorder is characterised by increased liver glycogen with a normal structure and no increase in serum glucose after oral intake of a protein-rich diet. Deficiency of which of the following enzymes is responsible for this disorder?
Your Answer: Glucose-6-phosphatase
Explanation:The most common glycogen storage disorder is von Gierke’s disease or glycogen storage disease type I. It results from a deficiency of enzyme glucose-6-phosphatase which affects the ability of liver to produce free glucose from glycogen and gluconeogenesis; leading to severe hypoglycaemia. There is also increased glycogen storage in the liver and kidneys causing enlargement and various problems in their functioning. The disease also causes lactic acidosis and hyperlipidaemia. The main treatment includes frequent or continuous feedings of corn-starch or other carbohydrates.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 37
Correct
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A 62-year-old male patient in the intensive care unit was found to have a low serum phosphate level. What is the serum level of phosphate which is considered as normal in adults?
Your Answer: 0.8–1.45 mmol/l
Explanation:After calcium, phosphorus is the most plentiful mineral in the human body. It is an important and vital element which our body needs to complete many physiologic processes , such as filtering waste and repairing cells. Phosphorus helps with bone growth and approximately 85% of phosphate in the body is contained in bone. Phosphate is involved in energy storage, and nerve and muscle production. A normal range of plasma phosphate in adults teenagers generally from 0.8 mmol/l to 1.45 mmol/l. The normal range varies depending on age. Infants and children have higher phosphorus levels because more of this mineral is needed for their normal growth and bone development.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 38
Correct
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Which of the following associations is correctly matched with the body's defence mechanism in fighting infection?
Your Answer: Specific cellular mechanism → cytotoxic T cells
Explanation:The immune system has certain levels of defence against pathogens. First line includes simple barriers such as skin, mucosa and stomach acid that prevent the pathogen from entering into the body. If this barrier is breached then the innate immune system is activated which includes leukocytes (macrophages, neutrophils, mast cells, eosinophils, basophils, natural killer cells). If the pathogens invade the second layer of defence then the third layer, adaptive immunity is activated, which includes B and T lymphocytes. B cells provide a humoral response whereas cytotoxic T cells have specific cellular mechanisms. They maintain a memory of past infections and are activated faster following a recurrence.
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This question is part of the following fields:
- General
- Physiology
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Question 39
Correct
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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: 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 40
Incorrect
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A 26-year-old female patient had the following blood report: RBC count = 4. 0 × 106/μl, haematocrit = 27% and haemoglobin = 11 g/dl, mean corpuscular volume (MCV) = 80–100 fl, mean corpuscular haemoglobin concentration (MCHC) = 31–37 g/dl. Which of the following is correct regarding this patient’s erythrocytes:
Your Answer: Decreased MCV
Correct Answer: Normal MCV
Explanation:MCV is the mean corpuscular volume and it is calculated from the haematocrit and the RBC count. It is normally 90 fl. Mean corpuscular haemoglobin concentration (MCHC) [g/dl] = haemoglobin [g/dl]/haematocrit = 11/0.27 = 41 g/dl and is higher than normal range (32 to 36 g/dL).
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This question is part of the following fields:
- General
- Physiology
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Question 41
Correct
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If the blood flow is constant, oxygen extraction by tissues will show the greatest decrease due to which of the following interventions?
Your Answer: Tissue cooling
Explanation:With a constant blood flow to a given tissue bed, there will be an increase in oxygen extraction by the tissue with the following; an increase in tissue metabolism and oxygen requirements: warming (or fever), exercise, catecholamines and thyroxine. With cooling, the demand for oxygen decreases, leading to decreased oxygen extraction.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 42
Correct
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Mechanical distortion, and not K+ channels are responsible for distortion of which of the following structures?
Your Answer: Pacinian corpuscle
Explanation:Pacinian corpuscles are a type of mechanoreceptor, sensitive to deep pressure, touch and high-frequency vibration. The Pacinian corpuscles are ovoid and about 1 mm long. In the centre of the corpuscle is the inner bulb, which is a fluid-filled cavity with a single afferent unmyelinated nerve ending. Any deformation in the corpuscle causes the generation of action potentials by opening of pressure-sensitive sodium ion channels in the axon membrane. This allows influx of sodium ions, creating a receptor potential (independent of potassium channels).
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This question is part of the following fields:
- Neurology
- Physiology
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Question 43
Correct
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Which of these structures is most likely to be damaged if a patient loses consciousness days or weeks after an otherwise insignificant head trauma, especially in elderly patients?
Your Answer: Dural bridging vein
Explanation:A subdural haematoma is a type of hematoma, usually associated with traumatic brain injury, in which blood collects between the dura mater and the pia-arachnoid mater. Symptoms of subdural haemorrhage have a slower onset than those of epidural haemorrhages because the lower pressure veins bleed more slowly than arteries. These injuries are more common in elderly patients, especially those taking antiplatelet or anticoagulant drugs. Oedema and increased intracranial pressure are unusual.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 44
Correct
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After severe injury of the upper limb following an accident. The humerus is injured as well as the nerve which innervates the muscles of the anterior compartment of the arm. Which nerve is injured?
Your Answer: Musculocutaneous
Explanation:The musculoskeletal nerve supplies the muscles of the anterior compartment of the arm including the coracobrachialis, biceps brachii and the greater part of the brachialis. This nerve derives its fibres from the fifth, sixth and seventh cervical nerves and arises from the lateral cord of the brachial plexus. It also provides a branch to the elbow joint.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 45
Correct
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A 16 year-old boy was stabbed in the right supraclavicular fossa. The sharp object punctured the portion of the parietal pleura that extends above the first rib. What is the name of this portion of the parietal pleura?
Your Answer: Cupola
Explanation:Endothoracic fascia: the connective tissue (fascia) that is between the costal parietal pleura and the inner wall of the chest wall.
Costomediastinal recess: the point where the costal pleura becomes mediastinal pleura.
Costodiaphragmatic recess: is the lowest point of the pleural sac where the costal pleura becomes diaphragmatic pleura.
Cupola: the part of the parietal pleura that extends above the first rib level into the root of the neck.
Costocervical recess: this is a made-up term.
Peritracheal fascia: a layer of connective tissue that invests the trachea.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 46
Incorrect
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The cranial nerves of the brain provide motor and sensory innervation to the structures of the head and neck. Which of the following cranial nerves provide only motor innervation?
Your Answer: Trigeminal
Correct Answer: Abducens
Explanation:The cranial nerves emerge directly from the brain and the brain stem. They provide sensory, motor or both motor and sensory innervation. Here is a summary of the cranial nerves and their function:
Olfactory – Purely sensory
Optic – Sensory
Oculomotor – Mainly motor
Trochlear – Motor
Trigeminal – Both sensory and motor
Abducens – Mainly motor
Facial – Both sensory and motor
Vestibulocochlear – Mostly sensory
Glossopharyngeal – Both sensory and motor
Vagus – Both sensory and motor
Accessory – Mainly motor
Hypoglossal – Mainly motor
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 47
Correct
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A 23 year old woman is Rh -ve and she delivered a baby with a Rh+ blood group. What measure can be performed to prevent Rh incompatibility in the next pregnancy?
Your Answer: Immunoglobulin D
Explanation:Rh disease is also known as erythroblastosis fetalis and is a disease of the new-born. In mild states it can cause anaemia with reticulocytosis and in severe forms causes severe anaemia, morbus hemolytcus new-born and hydrops fetalis. RBCs of the Rh+ baby can cross the placenta and enter into the maternal blood. As she is Rh- her body will form antibodies against the D antigen which will pass through the placenta in subsequent pregnancies.
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This question is part of the following fields:
- General
- Physiology
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Question 48
Correct
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A cerebellar tremor can be differentiated from a Parkinsonian tremor in that:
Your Answer: It only occurs during voluntary movements
Explanation:Cerebellar disease leads to intention tremors, which is absent at rest and appears at the onset of voluntary movements. In comparison, Parkinson’s tremor is present at rest. Frequency of tremor is a less reliable means to differentiate between the two as the oscillation amplitude of the tremor is not constant throughout a voluntary action.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 49
Incorrect
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The mechanism of action of streptokinase involves:
Your Answer: Activation of factor X
Correct Answer: Direct conversion of plasminogen to plasmin
Explanation:Streptokinase is an enzyme that is produced by group A beta haemolytic streptococcus and is an effective and cost efficient method for the dissolution of a clot used in cases of MI and pulmonary embolism. It works by directly converting plasminogen to plasmin which breaks down the blood components in the clot and fibrin, dissolving the clot. Streptokinase is a bacterial product and thus the body will develop immunity against it.
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This question is part of the following fields:
- General
- Physiology
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Question 50
Correct
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Cancer of the testis most likely metastases to which set of lymph nodes?
Your Answer: Aortic
Explanation:The lymphatic drainage of an organ is related to its blood supply. The lymphatic drainage of the testis drains along the testicular artery to reach the lymph nodes along the aorta.
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This question is part of the following fields:
- Endocrine
- Pathology
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Question 51
Correct
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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: 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 52
Incorrect
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Which of the following is a true statement regarding secretion of gastric acid?
Your Answer: Acetylcholine decreases gastric acid secretion
Correct Answer: Acetylcholine increases gastric acid secretion
Explanation:Gastric acid secretion is increased by acetylcholine, histamine and gastrin, with the help of cAMP as a secondary messenger. They increase H+ and Cl- secretion by increasing the number of H+/K+ ATPase molecules and Cl- channels. In contrast, gastric acid secretion is decreased by somatostatin, epidermal growth factor and prostaglandins.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 53
Correct
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A 76-year-old woman is diagnosed with diabetes mellitus after a urine test revealed she has glucosuria. Glucosuria may occur due to inadequate glucose reabsorption at:
Your Answer: Proximal convoluted tubule
Explanation:Glucose is reabsorbed almost 100% via sodium–glucose transport proteins (apical) and GLUT (basolateral) in the proximal convoluted tubule. Glycosuria or glucosuria is a condition of osmotic diuresis typical in those suffering from diabetes mellitus. Due to a lack of insulin, plasma glucose levels are above normal. This leads to saturation of receptors in the kidneys and glycosuria usually at plasma glucose levels above 11 mmol/l. Rarely, glycosuria is due to an intrinsic problem with glucose reabsorption within the kidneys (such as Fanconi syndrome), producing a condition termed renal glycosuria.
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This question is part of the following fields:
- Physiology
- Renal
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Question 54
Correct
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The fundus of the stomach receives blood supply from the same artery as the greater curvature of the stomach. Which of the following arteries when ligated will disrupt blood supply to the fundus of the stomach through this artery?
Your Answer: Splenic
Explanation:The fundus of the stomach along with the greater curvature of the stomach receive blood supply from the short gastric artery. The short gastric artery arises from the end of the splenic artery. The ligation of the splenic artery therefore would cause a disruption of blood supply to the fundus of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 55
Correct
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A 73-year-old woman goes to the doctor complaining of pain and stiffness in her shoulders and hips for 4 months, which is worst in the mornings. She has also been suffering from fatigue, weight loss and depression. There were no abnormal findings on physical examination. The erythrocyte sedimentation rate was 110 mm/hour, and serum rheumatoid factor and antinuclear antibody assays were negative. Mild normochromic normocytic anaemia was also found. What is the most likely diagnosis in this case?
Your Answer: Polymyalgia rheumatica
Explanation:Polymyalgia rheumatica (PMR) affects older adults, with an acute or subacute onset. Symptoms include severe pain and stiffness of the neck and pectoral or pelvic girdles, which is worse in the morning or after a period of inactivity and is usually bilateral. Other symptoms can include fatigue, weight loss, depression and fever. The erythrocyte sedimentation rate is usually elevated, and normochromic normocytic anaemia can occur. Other tests are usually normal in this disease.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 56
Correct
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A young male was diagnosed with hepatitis A, which clinically resolved in 2 weeks. What will his liver biopsy done after 6 months show?
Your Answer: Normal architecture
Explanation:Hepatitis A is the most common acute viral hepatitis, more common in children and young adults. It is caused by Hepatitis A virus, which is a single-stranded RNA picornavirus. The primary route of spread of Hepatitis A is the faecal-oral route. Consumption of contaminated raw shellfish is also a likely causative factor. The shedding of the virus in faecal matter occurs before the onset of symptoms and continues a few days after. Hepatitis A does not lead to chronic hepatitis or cirrhosis, and there is no known chronic carrier state. Hence, a biopsy performed after recovery will show normal hepatocellular architecture.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 57
Correct
-
The basilar artery arises from the confluence of which two arteries?
Your Answer: Vertebral
Explanation:The basilar artery is part of the vertebrobasilar system. It is formed by the confluence of the two vertebral arteries which arise from the subclavian arteries. These two vertebral arteries merge at the level of cranial nerve VI at the junction between the pons and the medulla oblangata to form what is know as the basilar artery. This vertebrobasilar system supplies the upper spinal cord, brainstem, cerebellum, and posterior part of brain.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 58
Correct
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Injury to which of the following arteries is likely to affect the blood supply to the seminal vesicles?
Your Answer: Middle rectal
Explanation:Ligation of middle rectal artery is most likely to affect the blood supply of seminal vesicles since arteries supplying the seminal vesicles are derived from the middle and inferior vesical and middle rectal arteries.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 59
Correct
-
Thalamic syndrome will most likely result in:
Your Answer: Hyperaesthesia
Explanation:Signs and symptoms of thalamic syndrome include contralateral hemi anaesthesia, burning or aching sensation in one half of a body (hyperaesthesia), often accompanied by mood swings.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 60
Correct
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A neurotransmitter of the nigrostriatal pathway is:
Your Answer: Dopamine
Explanation:Dopamine acts as a neurotransmitter in the brain, activating dopamine receptors. It is also a neurohormone released from the hypothalamus. It plays an important role in the reward system. It is believed that dopamine provides a teaching signal to parts of the brain responsible for acquiring new motor sequences (behaviours), by activation of dopamine neurons when an unexpected reward is presented. Loss of dopamine neurones in the nigrostriatal pathway causes Parkinson’s disease. In the frontal lobes, dopamine controls the flow of information from other areas of the brain, and thus, dopamine disorders in this region can cause a decline in neurocognitive functions, especially memory, attention and problem solving. Reduced dopamine concentrations in the prefrontal cortex are thought to contribute to attention-deficit disorder and some symptoms of schizophrenia. Dopamine is also the primary neuroendocrine regulator of the secretion of prolactin from the anterior pituitary gland. Dopamine is also commonly associated with the pleasure system of the brain. This plays a key role in understanding the mechanism of action of drugs (such as cocaine and the amphetamines), which seem to be directly or indirectly related to the increase of dopamine.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 61
Correct
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The wound healing process is documented in patients undergoing laparoscopic procedures. The port incisions are sutured closed and the wounds observed every few weeks for re-epithelialisation and tensile strength. Which substance is mostly likely to be found at a cellular level involved in wound healing?
Your Answer: Tyrosine kinase
Explanation:Cell surface growth factor receptors require intercellular proteins such as tyrosine kinase which are necessary to initiate a series of events that eventually lead to cell division and growth. Tyrosine kinase is an enzyme that transfers a phosphate group to the tyrosine residue in a protein. This phosphorylation will lead to an up regulation of the enzyme activity.
Fibronectin acts in the extracellular matrix to bind macromolecules (such as proteoglycans) via integrin receptors to aid attachment and migration of cells.
Laminin is an extracellular matrix component that is abundant in basement membranes.
Hyaluronic acid is one of the proteoglycans in the extracellular matrix.
Collagen fibres are part of the extracellular matrix that gives strength and stability to connective tissues.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 62
Correct
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A 45-year old farmer was referred to the surgical clinic with complaints of pain in his right hypochondrium. Investigations confirmed the diagnosis of hepatocellular carcinoma with malignant ascites. According to you, what is the most likely cause of HCC in this patient?
Your Answer: Aflatoxin
Explanation:Aflatoxins are naturally occurring toxins produced by the Aspergillus fungus (most often, A. flavus and A. parasiticus). These organisms are common and their native habitat is soil, decaying vegetation and grains. They can contaminate the grain before harvest or after storage, more likely in high-humidity (at least 7%) or high temperature environment of after stressful conditions like drought. Aflatoxins are mycotoxins and also carcinogenic. They get metabolized in the liver to an epoxide, aflatoxin M1. High exposure can lead to acute necrosis, cirrhosis or liver carcinoma. These substances can cause haemorrhage, acute liver damage, oedema, and alteration in digestion, absorption and/or metabolism of nutrients. Although humans are susceptible to these toxins like all other animals, they have a high tolerance level and hence, rarely develop acute aflatoxicosis. However, children are particularly susceptible to exposure leading to growth impairment and delayed development. Chronic exposure carries a high risk of hepatic cancer, due to intercalation of its metabolite aflatoxin M1 into the DNA and alkylation of the bases because of its epoxide moiety.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 63
Correct
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A 54 year old man fell off his bicycle. He felt a severe pain in his hand and wasn't able to move it. It was found that a carpal bone in the distal row was fractured. Which is the most likely bone?
Your Answer: Trapezium
Explanation:There are eight carpal bones which are arranged in two rows, proximal and distal; scaphoid, lunate, triquetral and pisiform are of proximal row. Trapezium, trapezoid, capitate and hamate are of the distal row.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 64
Correct
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13 year old girl developed sun burnt cheeks after spending the day playing on the beach. What is the underlying mechanism to her injury?
Your Answer: Free radical injury
Explanation:Free radicals are a by-product of chemical reactions with an unpaired electron in their outer most shell. They are capable of causing wide spread damage to cells. They can cause autolytic reactions thereby converting the reactants into free radicals. By absorbing sun light, the energy is used to hydrolyse water into hydroxyl (OH) and hydrogen (H) free radicals which can cause injury by lipid peroxidation of membranes, oxidative modification of proteins and damage to the DNA structure.
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This question is part of the following fields:
- Cell Injury & Wound Healing; Dermatology
- Pathology
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Question 65
Correct
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A 34-year-old woman has been suffering from headaches, fever, vomiting, and confusion for the last 5 days. A CT scan reveals an oedematous mass with ring enhancement in the left temporal region. It is biopsied, revealing glial cells, necrosis, neutrophils and lymphocytes. What is the most likely diagnosis?
Your Answer: Cerebral abscess
Explanation:A cerebral abscess can result from direct extension of cranial infections, penetrating head trauma, haematogenous spread, or for unknown causes. An abscess forms when an area of cerebral inflammation becomes necrotic and encapsulated by glial cells and fibroblasts. Oedema around the abscess can increase the intracranial pressure. Symptoms result from increased intracranial pressure and mass effects. It is most frequent in the third decade of life, and when it occurs in children, it is usually associated with congenital heart disease.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 66
Correct
-
A 13-year-old girl has complained of pain in her left arm for 4 months. An X-ray reveals a mass along with erosion of the affected humerus. Histologically, the tumour is found to be formed by small, round, blue cells. What is the most likely diagnosis?
Your Answer: Ewing’s sarcoma
Explanation:Ewing’s sarcoma is formed by small, round, blue cells, and is common in children. The usually develop in limbs, and clinical findings include pain and inflammation, with lytic destruction showing up on X-rays.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 67
Incorrect
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Which is the site of action of the drug omeprazole?
Your Answer: Na+/K+ pump
Correct Answer: H+/K+ ATPase
Explanation:H+/K+-ATPase or ‘proton pump’ located in the canalicular membrane plays a major role in acid secretion. The ATPase here is magnesium-dependent. Omeprazole is a proton pump inhibitor and blocks H+/K+- ATPase.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 68
Correct
-
What is the most likely condition a new born infant is likely to suffer from, if he/she was born with incomplete fusion of the embryonic endocardial cushions?
Your Answer: An atrioventricular septal defect
Explanation:The endocardial cushions in the heart are the mesenchymal tissue that make up the part of the atrioventricular valves, atrial septum and ventricular septum. An incomplete fusion of these mesenchymal cells can cause an atrioventricular septal defect. The terms endocardial cushion defect, atrioventricular septal defect and common atrioventricular canal defect can be used interchangeably with one another.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 69
Correct
-
A medical intern wanting to perform her first thoracentesis (remove fluid from the pleural cavity) wishes to be reminded where to insert the needle to aspirate in order to avoid injuring the lung or neurovascular elements. Where is this place?
Your Answer: The bottom of interspace 9 in the midaxillary line
Explanation:Thoracentesis is performed in the costodiaphragmatic recess. The needle needs to be inserted below the level of the lungs to avoid injury to the lungs. At the paravertebral line, is between ribs 10 and 12, at the midaxillary line between ribs 8 and 10 and at the midclavicular line between interspaces 6 and 8. The needle should be inserted at the top of the rib (or the bottom of the interspace) to avoid damage to the neurovascular structures found below the rib running in the costal groove.
The recommended location for the needle insertion varies depending upon the source. It is critical that the patient hold his or her breath to avoid piercing of the lung.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 70
Correct
-
Chronic obstructive pulmonary disease (COPD) is likely to result in:
Your Answer: Respiratory acidosis
Explanation:COPD leads to respiratory acidosis (chronic). This occurs due to hypoventilation which involves multiple causes, such as poor responsiveness to hypoxia and hypercapnia, increased ventilation/perfusion mismatch leading to increased dead space ventilation and decreased diaphragm function.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 71
Correct
-
Risk factors for hepatocellular carcinoma do NOT include:
Your Answer: Heptitis E
Explanation:Risk factors for hepatocellular carcinoma include hepatitis B and C, aflatoxin, anabolic steroids, alcohol cirrhosis and primary liver disease.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 72
Correct
-
Which of the following is a likely cause of jaundice?
Your 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 73
Incorrect
-
Which of the following is a landmark to identify the site of the 2nd costal cartilage?
Your Answer: Sternoclavicular joint
Correct Answer: Sternal angle
Explanation:The sternal angle is an important part where the second costal cartilage attaches to the sternum. Finding the sternal angle will help in finding the second costal cartilage and intercostal space.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 74
Correct
-
Which of the following key features will be seen in an organ undergoing atrophy?
Your Answer: A greater number of autophagic vacuoles
Explanation:Atrophy is characterised by the breakdown of intracellular components along with organelles and packing them into vacuoles known as autophagic vacuoles. This is an adaptive response that separates the damaged cellular structures from the rest of the cells.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 75
Correct
-
A 27-year-old woman, who had been taking a combined oral contraceptive for 6 months, presented with inguinal pain and oedema of the left leg. Which of the following investigations would you recommend to help confirm the diagnosis?
Your Answer: Duplex scan
Explanation:Oral combined contraceptive pill (OCCP) is a drug used for birth control and treating a number of other conditions. Women who take the OCP have a higher risk of developing deep vein thrombosis (DVT), usually in the legs. Duplex ultrasonography is a safe and non-invasive technique which is used for diagnosing the presence of lower extremity thrombi.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 76
Correct
-
Gastrocnemius, semimembranosus and semitendinosus together with which other muscle form the boundaries of the popliteal fossa?
Your Answer: Biceps femoris
Explanation:The popliteal fossa is located at the back of the knee. It is bounded laterally by the biceps femoris above and the plantaris and lateral head of the gastrocnemius below and medially by the semitendinosus and semimembranosus above and by the medial head of the gastrocnemius below.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 77
Correct
-
The dilator pupillae muscle is innervated by postganglionic sympathetic fibres. Where do the postganglionic sympathetic fibres originate?
Your Answer: Superior cervical ganglion
Explanation:The postganglionic sympathetic axons are derived from the superior cervical ganglion and innervate the eye and lacrimal gland allowing for vasoconstriction of the iris and sclera, pupillary dilation, widening of the palpebral fissure, and a reduction in tear production.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 78
Correct
-
A 27-year-old woman has chronic low serum calcium levels. Which of the following conditions may be responsible for the hypocalcaemia in this patient?
Your Answer: Hypoparathyroidism
Explanation:Chronic hypocalcaemia is mostly seen in patients with hypoparathyroidism as a result of accidental removal or damage to parathyroid glands during thyroidectomy.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 79
Incorrect
-
Which of these nerves controls adduction of hand?
Your Answer: Median nerve
Correct Answer: Ulnar nerve
Explanation:The adductors of the fingers are the palmer interossei. They are supplied by the ulnar nerve, which is a branch of the medical cord of the brachial plexus.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 80
Correct
-
Which type of thyroid tumour represents 75 - 80% of thyroid cancer cases? This type is predominant in children and in patients who have had a previous history of head or neck radiation.
Your Answer: Papillary carcinoma
Explanation:Papillary thyroid carcinoma is the most common thyroid cancer. This cancer has a high cure rate with 10-year survival rates for all patients with papillary thyroid cancer estimated at 80% to 90%.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 81
Correct
-
What is the result of maltase deficiency in the brush border of the small intestine?
Your Answer: Results in increased passage of maltose in stool
Explanation:Maltase is an enzyme produced from the surface cells of the villi, lining the small intestine and aids in hydrolysing the disaccharide maltose, which splits into two molecules of α-glucose. It is done by breaking the glycosidic bond between the ‘first’ carbon of one glucose and the ‘fourth’ carbon of the other (a 1–4 bond). Hence, a deficiency of enzyme maltase will result in the increased passage of maltose in the stool.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 82
Correct
-
The Brunner glands secrete an alkaline product that helps maintain an optimal pH for pancreatic enzyme activity. Where are these glands located?
Your 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 83
Correct
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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: 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 84
Correct
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The pterion is clinically significant as it marks an area of weakness on the skull. What structure lies beneath it?
Your Answer: Anterior branches of the middle meningeal artery
Explanation:The pterion is the area where four bones, the parietal, frontal, greater wing of sphenoid and the squamous part of the temporal bone meet. It overlies the anterior branch of the middle meningeal artery on the internal aspect of the skull. The pterion is the weakest part of the skull. Slight trauma to this region can cause extradural hematoma.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 85
Incorrect
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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: 65 mg/min
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 86
Correct
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A 30-year-old woman known with Von Willebrand disease (vWD) has to undergo surgery. Which of these complications is most unlikely in this patient?
Your Answer: Hemarthrosis
Explanation:Von Willebrand disease (vWD) is an inherited haemorrhagic disorder characterised by the impairment of primary haemostasis. It is caused by the deficiency or dysfunction of a protein named von Willebrand factor. The most common manifestation due to the condition is abnormal bleeding. Complications include easy bruising, hematomas, epistaxis, menorrhagia, prolonged bleeding and severe haemorrhage. Hemarthrosis is a complication that is more commonly found in haemophilia.
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This question is part of the following fields:
- Haematology
- Pathology
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Question 87
Correct
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A young female in the 15th week of pregnancy presented to the emergency department with the passage of grape-like masses per vagina. Dilatation and curettage was done and microscopy revealed large avascular villi with trophoblastic proliferation. Which one of the following investigations is best recommended for her follow-up?
Your Answer: Serum β-hCG
Explanation:Trophoblast is the layer of cells surrounding the blastocyst and that later develops into the chorion and amnion. Gestational trophoblastic disease is a tumour arising from this trophoblast. It can occur during or after either an intrauterine or ectopic pregnancy. If it occurs in a pregnant woman, it usually leads to spontaneous abortion, eclampsia or fetal death. It can be either malignant or benign.
In suspected cases, investigations include measurement of serum beta subunit of human chorionic gonadotrophin (β-hCG) and pelvic ultrasound. Confirmatory test is a biopsy. Post-removal, the disease is classified clinically to assess further treatment. To assess the presence of metastases, further work-up includes computed tomography of the brain, chest, abdomen and pelvis. Chemotherapy is usually needed for persistent disease. If at least three consecutive, weekly serum β-hCG measurements are normal, treatment is considered successful. Follow-up is also done by measuring β-hCG.
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This question is part of the following fields:
- Pathology
- Women's Health
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Question 88
Correct
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A 32-year old gentleman came to the emergency department, complaining of progressively increasing weakness in his arms and legs over 5 days. On examination, there is symmetrical weakness on both sides of his face, along with weakness of the proximal and distal muscles of all four limbs. No loss of sensation noted. Deep tendon reflexes could not be elicited and plantar responses were downward. On enquiry, it was revealed that he had an upper respiratory tract infection 10 days ago. The likely diagnosis is:
Your Answer: Guillain–Barré syndrome
Explanation:Guillain–Barré syndrome (GBS) is an acute, autoimmune polyradiculoneuropathy which affects the peripheral nervous system and is usually triggered by an acute infectious process. 75% patients have a history of acute infection within the past 1–4 weeks, usually respiratory or gastrointestinal. immunisations have also been implicated. The most common form is acute inflammatory demyelinating polyneuropathy. It results in an ascending paralysis with complete loss of deep tendon reflexes. Treatment includes immunoglobulins and supportive care. However, the disease may be fatal due to severe pulmonary complications and dysautonomia.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 89
Correct
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If a patient takes long-term corticosteroid therapy, which of the following diseases is most likely to develop?
Your Answer: Osteoporosis
Explanation:One of the complications of long-term intake of corticosteroids is osteoporosis. Some guidelines recommend prophylactic calcium and vitamin D supplementation in patients who take more than 30 mg hydrocortisone or 7.5 mg of prednisolone daily.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 90
Correct
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A 38-year-old woman with end-stage renal disease, is undergoing haemodialysis. She has normocytic normochromic anaemia. What is the best treatment for her?
Your Answer: Erythropoietin
Explanation:E erythropoietin (EPO) is a hormone that is released by the kidney. It is responsible for the regulation of red blood cell production in the body. It can be made using recombinant technology and is used in the treatment of anaemia of chronic renal failure and in patients under going chemotherapy
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This question is part of the following fields:
- General
- Physiology
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Question 91
Correct
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Identify which of the following muscles acts on two joints?
Your Answer: Sartorius
Explanation:The sartorius muscle, the longest muscle in the body, is one of the two jointed or biarticular muscles. It originates from the anterior superior iliac spine and part of the notch between the anterior superior iliac spine and anterior inferior iliac spine and crosses both the hip joint and the knee joint. At the hip joint the sartorius flexes and rotates the thigh at the hip joint and flexes the leg at the knee joint.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 92
Correct
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A 62-year-old man presented with a persistent cough and weight loss. Chest x-ray demonstrated widespread nodular opacities. After a bronchoalveolar lavage, atypical cells were detected. Which is the most probable diagnosis?
Your Answer: Bronchioalveolar carcinoma
Explanation:Bronchioloalveolar carcinoma (BAC) is a term used to define a particular subtype of adenocarcinoma which develops in cells near the alveoli, in the outer regions of the lungs. On a chest X-ray it can appear as a single peripheral spot or as scattered spots throughout the lungs. Symptoms include cough, haemoptysis, chest pain, dyspnoea and loss of weight.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 93
Correct
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A 26-year old man is brought to the A&E with a stab wound to the chest. The wound is in a part of the left lung that might partially fill the costomediastinal recess in full respiration. Where did the weapon strike this man?
Your Answer: Lingula
Explanation:During full inspiration, the lingual-of the left lung partially fills the costomediastinal recess. If the apex of the lung is fully filled with air, it would occupy the copula (the part of the pleura that extends above the first rib). The hilum is part of the lung where the neurovascular structures that form the root of the lung enter and leave the lung and doesn’t expand on inspiration. The middle lobe can expand to fill the costomediastinal recess, however, the middle lobe is on the right lung. The inferior lobe, during full inspiration, might fill the costodiaphragmatic recess.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 94
Correct
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Diuretics that act on the ascending limb of the loop of Henle produce:
Your Answer: Reduced active transport of sodium
Explanation:The loop of Henlé leads from the proximal convoluted tubule to the distal convoluted tubule. Its primary function uses a counter current multiplier mechanism in the medulla to reabsorb water and ions from the urine. It can be divided into four parts:
1. Descending limb of loop of Henl̩ Рlow permeability to ions and urea, while being highly permeable to water
2. Thin ascending limb of loop of Henl̩ Рnot permeable to water, but it is permeable to ions
3. Medullary thick ascending limb of loop of Henlé – sodium (Na+), potassium (K+) and chloride (Cl–) ions are reabsorbed by active transport. K+ is passively transported along its concentration gradient through a K+ channel in the basolateral aspect of the cells, back into the lumen of the ascending limb.
4. The cortical thick ascending limb – the site of action where loop diuretics such as furosemide block the K+/Na+/2Cl− co-transporters = reduced active transport.
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This question is part of the following fields:
- Physiology
- Renal
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Question 95
Correct
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A 35-year-old woman in her 37th week of pregnancy complains of urinary incontinence. She is most likely to have:
Your Answer: Stress incontinence
Explanation:Urinary incontinence is the involuntary excretion of urine from one’s body. It is often temporary and it almost always results from an underlying medical condition. Several types include:
– Stress incontinence is the voiding of urine following increased abdominal pressure e.g. laughing, coughing, pregnancy etc. It is the most common form of incontinence in women, most commonly due to pelvic floor muscle weakness, physical changes from pregnancy, childbirth and menopause. In men it is a common problem following a prostatectomy. Most lab results such as urine analysis, cystometry and postvoid residual volume are normal.
– Urge incontinence is involuntary loss of urine occurring for no apparent reason while suddenly feeling the need or urge to urinate. The most common cause of urge incontinence are involuntary and inappropriate detrusor muscle contractions.
– Functional incontinence – occurs when a person does not recognise the need to go to the toilet, recognise where the toilet is or get to the toilet in time. The urine loss may be large. Causes of functional incontinence include confusion, dementia, poor eyesight, poor mobility, poor dexterity or unwillingness. t
– Overflow incontinence – sometimes people find that they cannot stop their bladders from constantly dribbling or continuing to dribble for some time after they have passed urine.
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This question is part of the following fields:
- Physiology
- Renal
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Question 96
Incorrect
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In the case of an injury to the sub sartorial canal, which of the following structures is most likely to be injured?
Your Answer: Popliteal artery
Correct Answer: Nerve to vastus medialis
Explanation:The adductor canal (sub sartorial canal) is situated in the middle third of the thigh.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 97
Correct
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Which lymph nodes are likely to be enlarged in a patient who has malignant growth involving the anus?
Your Answer: Superficial inguinal
Explanation:The lymphatics from the anus, skin of the perineum and the scrotum end in the superficial inguinal nodes. In case of a malignant growth of the anus, the superficial inguinal lymph nodes would most likely be enlarge.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 98
Correct
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A 40-year old woman with portal hypertension has impaired venous drainage of the anal canal above the pectinate line. Thus, there might be an increase in blood flow downward to the systemic venous system via anastomoses with the inferior rectal vein. This is a tributary of?
Your Answer: Internal pudendal vein
Explanation:The inferior rectal vein drains into the internal pudendal vein. In addition the external iliac vein is one of the two branches of the common iliac vein however the internal iliac vein and it’s tributaries (including the pudendal vein) are much more important in draining the pelvic structures.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 99
Incorrect
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Which is the most common benign germ-cell tumour that could occur in a premenopausal woman?
Your Answer: Mucinous cystadenoma
Correct Answer: Dermoid cyst
Explanation:A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature and solid tissues. Dermoid cysts grow slowly and this type of cystic teratoma is nearly always benign.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 100
Correct
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Which of these conditions is mithramycin used for?
Your Answer: Hypercalcaemia of malignancy
Explanation:Mithramycin or Plicamycin is a tricyclic pentaglycosidic antibiotic derived from Streptomyces strains. It inhibits RNA and protein synthesis by adhering to DNA. It is used as a fluorescent dye and as an antineoplastic agent. It is also used to reduce hypercalcaemia, especially caused by malignancy. Plicamycin is currently used in multiple areas of research, including cancer cell apoptosis and as a metastasis inhibitor.
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This question is part of the following fields:
- Pathology
- Pharmacology
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SESSION STATS - PERFORMANCE PER SPECIALTY
