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Question 1
Incorrect
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Which of the following foods contain Vitamin B 12?
Your Answer: Yellow vegetables and fruit
Correct Answer: Liver, meat
Explanation:No fungi, plants, nor animals (including humans) are capable of producing vitamin B12. Only bacteria and archaea have the enzymes needed for its synthesis. Proved food sources of B12 are animal products (meat, fish, dairy products).
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This question is part of the following fields:
- Haematology
- Physiology
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Question 2
Correct
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Which of the following is a method for measurement of cardiac output?
Your Answer: Indicator dilution method
Explanation:There are two methods of calculating the cardiac output in humans other than doppler with echocardiography: The direct Fick’s method and the indicator dilution method. In the indicator dilution technique, a known amount of a substance such as a dye or, more commonly, a radioactive isotope is injected into an arm vein and the concentration of the indicator in serial samples of arterial blood is determined. The output of the heart is equal to the amount of indicator injected divided by its average concentration in arterial blood after a single circulation through the heart.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 3
Correct
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A 45-year-old woman gives a two-week history of fatigue, muscle cramps, and paraesthesia of her fingers and toes. She has low serum calcium and low serum parathyroid hormone levels on investigations. She appears slightly confused, likely due to hypocalcaemia, and cannot give a full account of her past medical history, but can recall that she recently was admitted to the hospital. What is the most likely cause of her hypoparathyroidism?
Your Answer: Thyroidectomy
Explanation:The most common cause of hypoparathyroidism is injury or removing the parathyroid glands. They can be injured accidentally during surgery to remove the thyroid as they are located posterior to the thyroid gland. A result of both low parathyroid hormone and low calcium is likely to mean that the parathyroid glands are not responding to hypocalcaemia. The hypocalcaemia can cause confusion, and the stay in the hospital is likely to refer to her surgery. While a parathyroid adenoma is fairly common and can cause hypoparathyroidism, it much more likely causes hyperparathyroidism. Chronic kidney disease is likely to cause hypocalcaemia, which would increase parathyroid hormone production in an attempt to increase calcium levels, causing hyperparathyroidism. Vitamin D is activated by the kidneys and then binds to calcium to be absorbed in the terminal ileum so that a deficiency would cause hyperparathyroidism.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 4
Incorrect
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Myocardial oxygen consumption is increased by:
Your Answer: By additional oxygen extraction from blood
Correct Answer: An increase in after load
Explanation:Cardiac oxygen consumption is directly related to the amount of tension that develops in the ventricles. It is increased by an increased size of heart, increased afterload, increased contractility and increased heart rate.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 5
Correct
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Under normal conditions (where n represents the number of chromosome pairs), just before mitosis begins, how many chromosomes are contained in the nucleus of each somatic cell:
Your Answer: 4n
Explanation:In a normal somatic cell there are 2n chromosome but in a replicating cell just before mitosis the chromosomes duplicate but are still joined via the centrosome. Thus there are 4n chromosomes. After completion of mitosis the number goes back to 2n.
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This question is part of the following fields:
- Genetics
- Physiology
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Question 6
Incorrect
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A 24 year old male sustained an insect bite and presents with a red hot arm and acute cellulitis has been diagnosed. The predominant white cells in this type of acute inflammation are:
Your Answer: Macrophages
Correct Answer: Neutrophils
Explanation:Neutrophil polymorphs are the predominant type of white cells in an acute reaction. They pass between endothelial cell junctions to invade damaged tissue so that the effects of injury can be combated. Extravasation occurs with the movement of leukocytes out of the vessel lumen, and is achieved in five phases which are margination, ‘rolling’, adhesion, transmigration and chemotaxis.
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This question is part of the following fields:
- Inflammatory Responses
- Pathology
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Question 7
Incorrect
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Emulsification of dietary lipids is brought about by
Your Answer: Cholecystokinin
Correct Answer: Bile salts
Explanation:Digestion of fats can begin in the mouth where lingual lipase breaks down some short chain lipids into diglycerides. However fats are mainly digested in the small intestine. The presence of fat in the small intestine produces hormones that stimulate the release of pancreatic lipase from the pancreas and bile from the liver which helps in the emulsification of fats for absorption of fatty acids.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 8
Incorrect
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Which of the following is a form of synaptic plasticity?
Your Answer: Déjà vu
Correct Answer: Working memory
Explanation:Synaptic plasticity is an important neurochemical foundation of working memory and generation of memory. Synaptic plasticity is the ability of synapses to strengthen or weaken over time in response to increases or decreases in their activity.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 9
Incorrect
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Which enzyme is deficient in the inborn error of metabolism called galactosemia?
Your Answer: Galactokinase
Correct Answer: Galactose-1-phosphate uridyl transferase
Explanation:Galactosaemia is a rare genetic autosomal recessive metabolic disorder. Lactose is broken down by the enzyme lactase into glucose and galactose. In individuals with galactosemia, the enzymes needed for further metabolism of galactose (Galactose-1-phosphate uridyltransferase) are severely diminished or missing entirely, leading to toxic levels of galactose 1-phosphate in various tissues.
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This question is part of the following fields:
- Metabolism
- Physiology
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Question 10
Incorrect
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All of the following are Vitamin K-dependent clotting factors except:
Your Answer: Protein S
Correct Answer: Factor XI
Explanation:Activated vitamin K is used to gamma carboxylate (and thus activate) certain enzymes involved in coagulation: Factors II, VII, IX, X, and protein C and protein S. Inability to activate the clotting cascade via these factors leads to the bleeding symptoms
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This question is part of the following fields:
- Haematology
- Physiology
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Question 11
Incorrect
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In a normal heart rate at rest, the left ventricular end-diastolic volume is ….
Your Answer: 70-100 ml
Correct Answer: 100-130 ml
Explanation:In cardiovascular physiology, end-diastolic volume (EDV) is the volume of blood in the right and/or left ventricle at end load or filling in (diastole) or the amount of blood in the ventricles just before systole. Because greater EDVs cause greater distention of the ventricle, EDV is often used synonymously with preload, which refers to the length of the sarcomeres in cardiac muscle prior to contraction (systole). End-diastolic volume: Right = 144 mL(± 23mL) & Left = 142 mL (± 21 mL).
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 12
Incorrect
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Which of the following values of bone mineral density measured by DEXA would signify osteopenia?
Your Answer: T score of -0.9
Correct Answer: T score of -2.2
Explanation:DEXA T Scores:Normal T-score ≥ −1.0Osteopenia −2.5 < T-score < −1.0Osteoporosis T-score ≤ −2.5Severe osteoporosis T-score ≤ −2.5 with fragility fracture
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 13
Correct
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At rest, proton pumps are sequestered within the parietal cell in a series of membrane compartments known as:
Your Answer: Tubulovesicles
Explanation:The gastric H, K-ATPase pump, which pumps gastric acid (HCl), in the resting state is found in cytoplasmic tubular membranes. In the stimulated state this pump moves from the tubulovesicles to the apical membrane.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 14
Incorrect
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What is the three main structures in the portal triad ( portal space )?
Your Answer: The sinusoids , branch of hepatic artery, branch of portal vein
Correct Answer: Branch of hepatic artery, branch of portal vein, bile ductules
Explanation:A portal triad (also known as portal field, portal area, or portal tract) is a distinctive arrangement in the liver. It is a component of the hepatic lobule. It consists of the following five structures:- Proper hepatic artery- Hepatic portal vein- Common bile duct- Lymphatic vessels- Branch of the vagus nerve
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This question is part of the following fields:
- Hepatobiliary
- Physiology
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Question 15
Incorrect
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The ostium of the maxillary sinus opens into which of the following structures?
Your Answer: Superior meatus
Correct Answer: Middle meatus
Explanation:The maxillary sinuses usually develop symmetrically. The maxillary sinus ostium drains into the infundibulum which joins the hiatus semilunaris and drains into the middle meatus.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 16
Incorrect
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Which one of the following is most likely to be seen in a patient with multiple endocrine neoplasia (MEN) type I?
Your Answer: Medullary thyroid carcinoma
Correct Answer: Insulinoma
Explanation:Multiple endocrine neoplasia type 1 (MEN-1 syndrome) or Wermer’s syndrome is part of a group of disorders, the multiple endocrine neoplasias, that affect the endocrine system through development of neoplastic lesions in the ‘three P’s’:Parathyroid (>90%): hyperparathyroidism due to parathyroid hyperplasiaPituitary (15-42%)Pancreas (60-70%, e.g. insulinoma, gastrinoma)
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 17
Correct
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Which of the following cells are attracted to the surface of endothelium by selectins?
Your Answer: Neutrophils
Explanation:Selectins are expressed on the surface of the endothelium. P selectins are released from weibel-palade bodies and E selectins are induced by cytokines (TNF and IL-1). They bind to receptors on the neutrophils called saiyl lewis X.
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This question is part of the following fields:
- Immunology
- Physiology
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Question 18
Incorrect
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90% of erythropoietin necessary for haemopoesis is produced by the kidneys, the remainder is formed in the?
Your Answer: Bone marrow
Correct Answer: Liver
Explanation:Erythropoietin is produced by interstitial fibroblasts in the kidney in close association with peritubular capillary and proximal convoluted tubule. It is also produced in perisinusoidal cells in the liver. While liver production predominates in the fetal and perinatal period, renal production is predominant during adulthood.
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This question is part of the following fields:
- Haematology
- Physiology
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Question 19
Incorrect
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Which of the following is a precursor to the tissue macrophage?
Your Answer: Neutrophil
Correct Answer: Monocyte
Explanation:Monocytes are a type of white blood cell, or leukocyte. They are the largest type of leukocyte and can differentiate into macrophages or dendritic cells.
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This question is part of the following fields:
- Haematology
- Physiology
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Question 20
Incorrect
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If O2 makes up 21% of air, then at one atmosphere (760mmHg) it would be expected that the PO2 of inspired air should be 0,21 x 760 = 160mmHg. In the alveoli the actual measure is 149mmHg because…
Your Answer: N2 diffuses easily
Correct Answer: Water is equilibrated with air
Explanation:There are several factors that determine the value of alveolar partial oxygen pressure including: the pressure of outside air, the partial pressure of inspired oxygen and carbon dioxide, the rates of total body oxygen consumption and carbon dioxide production, the rates of alveolar ventilation and perfusion. The alveolar partial pressure is lower than the atmospheric oxygen partial pressure. One reason is, as the air enters the lungs, it is humidified by the upper airway and thus the partial pressure of water vapour reduces the oxygen partial pressure as water is equilibrated with air.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 21
Correct
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In adults, there are normally how many teeth:
Your Answer: 32
Explanation:In adults, there are 32 teeth, 16 in the upper jaw and 16 in the lower jaw. On each side in both upper and lower arches, there are two incisors, one canine, two premolars and three molar teeth.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 22
Incorrect
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How many unpaired branches leave the abdominal aorta to supply the abdominal viscera?
Your Answer: One
Correct Answer: Three
Explanation:The abdominal arteries are divided into 3 branches;- 3 main unpaired trunks (celiac trunk, superior mesenteric, inferior mesenteric arteries)- 6 paired branches- unpaired median sacral artery.We can group the abdominal aorta as follows;-Ventral which includes: Coeliac trunk, superior mesenteric and inferior mesenteric arteries-Lateral: Inferior phrenic, middle suprarenal, renal and gonadal arteries-Dorsal: Lumbar and median sacral arteries-Terminal : Right and left common iliac arteriesThe celiac trunk (L1) takes blood the foregut and its found posterior to the stomach. The unpaired superior mesenteric artery supplies blood to the mid-gut. The paired renal arteries form the inferior suprarenal arteries. The renal arteries arise around L1/L2 and takes blood to either side of the kidneys. The median sacral artery supplies blood to the lumbar vertebrae the L4 and L5.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 23
Correct
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The breakdown of superoxide is catalysed by which enzyme?
Your Answer: Superoxide dismutase
Explanation:As superoxide is toxic, nearly all organisms living in the presence of oxygen contain isoforms of the superoxide-scavenging enzyme superoxide dismutase, or SOD. SOD is an extremely efficient enzyme; it catalyses the neutralization of superoxide nearly as quickly as the two can diffuse together spontaneously in solution.
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This question is part of the following fields:
- Cell Biology
- Physiology
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Question 24
Incorrect
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A patient with chronic renal disease, missed a day of his dialysis schedule., His serum potassium was 7.6 mmol/L when his electrolytes were checked. What is the ECG finding expected in this patient?
Your Answer: Prolonged QT interval
Correct Answer: Tented T waves
Explanation:ECG characteristics of hyperkalaemia may show the following changes: P-waves are widened and of low amplitude due to slowing of conduction, widened QRS complex, QRS-T fusion, loss of ST segment and tall tented T waves.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 25
Incorrect
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Question 26
Incorrect
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Regarding the closure of the ductus arteriosus (DA) after birth which of the following most accurately describes the mechanisms leading to closure of the DA?
Your Answer: Increased arterial pO2, decreased bradykinin & decreased Prostaglandin E2
Correct Answer: Increased arterial pO2, increased bradykinin & decreased Prostaglandin E2
Explanation:Functional closure of the ductus arteriosus is neonates is completed within the first few days after birth. It normally occurs by the 12th postnatal week. It has been suggested that persistent patency of DA results from a failure of the TGF-B induction after birth. Due to increased arterial pO2, constriction of the DA occurs. In addition to this on inflation the bradykinin system is activated with cause the smooth muscles in the DA to constrict. A decrease in the E2 prostaglandin is also an important factor as raised levels have been indicated in keeping the patency of the DA.
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This question is part of the following fields:
- Anatomy
- Embryology
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Question 27
Correct
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What will the destruction of endoplasmic reticulum stop?
Your Answer: Synthesis of proteins
Explanation:The rough endoplasmic reticulum is the factory for the manufacturing of proteins. It contains ribosomes attached to it and transports proteins that are destined for membranes and secretions. The rough ER is connected to the nuclear envelope and to the cisternae of the Golgi apparatus by vesicles that shuttle between the two compartments.
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This question is part of the following fields:
- Cell Biology
- Physiology
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Question 28
Incorrect
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Where is the mental foramen located?
Your Answer: In the maxilla
Correct Answer: In the mandible
Explanation:The mental foramen is found bilaterally on the anterior surface of the mandible adjacent to the second premolar tooth. The mental nerve and terminal branches of the inferior alveolar nerve and mental artery leave the mandibular canal through it.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 29
Correct
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Which of the following limits the duration of inspiration and increases respiratory rate:
Your Answer: Pneumotaxic centre
Explanation:The mechanism of control of ventilation is an interplay of multiple regions in the brain. The medullary respiratory centre sets the basic rhythm of breathing and the pons modifies the output of the medullary centres. There are two pontine centres: apneustic and pneumotaxic. The pnuemotaxic centre controls inspiratory time. Increased signals to this area increases respiratory rate. The dorsal respiratory group (DRG) integrates input from the stretch receptors and the chemoreceptors in the periphery and is composed mainly of inspiratory neurons. The DRG controls the basic rhythm of breathing by triggering inspiratory impulses. The ventral respiratory group (VRG) generates breathing rhythm and integrates data coming into the medulla and contains both inspiratory and expiratory neurons. They are primarily active in exercise and stress.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 30
Incorrect
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Which membrane bound protein in the sarcoplasmic reticulum regulates calcium return from the cytosol to the sarcoplasmic reticulum?
Your Answer: Camp
Correct Answer: Phospholamban
Explanation:Phosphorylation of phospholamban increases calcium ATPase activity and sequestration of calcium in the sarcoplasmic reticulum. An increased rate of relaxation is explained because cAMP also activates the protein phospholamban, situated on the membrane of the sarcoplasmic reticulum (SR), that controls the rate of uptake of calcium into the SR. The latter effect explains enhanced relaxation (lusitropic effect).
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 31
Incorrect
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A 32-year-old female is found to have a thyroglossal cyst that has been recently infected and the patient requests treatment. What is the most appropriate course of action?
Your Answer: Excision of the cyst alone with ligation of the track
Correct Answer: Surgical treatment with resection of cyst, associated track, central portion of the hyoid and wedge of tongue muscle behind the hyoid
Explanation:A thyroglossal duct cyst (TGDC) is the most common mass found in the midline of the neck. The mass is usually located at or below the level of the hyoid bone, although a TGDC can be located anywhere from the foramen cecum to the level of the thyroid gland.Most patients with a TGDC present with asymptomatic masses in the midline of the neck. Recurrent inflammation associated with infection of a TGDC is not uncommon. When an infection is present, the cyst often enlarges and an abscess may form. Spontaneous rupture with secondary sinus tract formation can also occur.The surgical treatment of choice for thyroglossal cysts is the Sistrunk operation, in which an en block resection of the sinus tract and above (including the midportion of the hyoid bone) is performed. Recurrence is approximately 3-5% and is increased by incomplete excision and a history of recurrent infections.
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This question is part of the following fields:
- Head & Neck
- Pathology
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Question 32
Incorrect
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Concerning surface anatomy, where is the apex beat found?
Your Answer: 6th intercostal space mid clavicular line
Correct Answer: 5th intercostal space mid clavicular line
Explanation:The location of the apex beat may vary but it is mostly found in the left 5th intercostal space 6 cm from the anterior median line or in the mid clavicular line.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 33
Incorrect
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Vitamin B12 is transported from the enterocytes to the bone marrow by which factor?
Your Answer: Vitamin b12-binding protein
Correct Answer: Transcobalamin II (TC IIi)
Explanation:B12 must be attached to IF for it to be efficiently absorbed, as receptors on the enterocytes in the terminal ileum of the small bowel only recognize the B12-IF complex. Once the IF/B12 complex is recognized by specialized ileal receptors, it is transported into the portal circulation. The vitamin is then transferred to transcobalamin II (TC-II/B12), which serves as the plasma transporter.
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This question is part of the following fields:
- Haematology
- Physiology
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Question 34
Incorrect
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Three adjacent nucleotides code for a particular amino acid. These are called codons. How many common amino acids are there and how many potential codon combinations make up the genetic code?
Your Answer: 12 amino acids, 64 codon combinations
Correct Answer: 20 amino acids, 64 codon combinations
Explanation:There are around 20 amino acids and 61 out of the 64 combinations of codon code for these 20 common amino acids.
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This question is part of the following fields:
- Genetics
- Physiology
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Question 35
Incorrect
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The energy needed for glycogen synthesis comes from which compound?
Your Answer: ATP
Correct Answer: UTP
Explanation:Glycogen synthesis is, unlike its breakdown, endergonic—it requires the input of energy. Energy for glycogen synthesis comes from uridine triphosphate (UTP)
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This question is part of the following fields:
- Metabolism
- Physiology
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Question 36
Incorrect
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Question 37
Incorrect
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Which of the following phases in depolarization and repolarization of cardiac muscle cells are caused by the inactivation of Na+ channels?
Your Answer: Phase 3 : resting membrane potential
Correct Answer: Phase 1 : rapid repolarization
Explanation:Phase 0 is caused by the sodium current. Voltage gated sodium channels open leading to the influx of sodium into the cardiac muscle cell. Phase 1 is the rapid transient repolarization phase which is caused by the inactivation of the voltage gated sodium channels and opening of the voltage gated potassium channels along with opening of the slow calcium channels. Phase 2 which is the plateau is caused by opening of the slow calcium channels. Phase 4 is caused by closing of the slow calcium channels and opening of the potassium channels leading to efflux of potassium leading to the establishment of the resting membrane potential.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 38
Incorrect
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Which of the following is responsible for transporting both glucose and fructose into the interstitium?
Your Answer: GLUT 1
Correct Answer: GLUT 2
Explanation:Absorption of glucose involves transport from the intestinal lumen, across the epithelium and into blood. The transporter that carries glucose and galactose into the enterocyte is the sodium-dependent hexose transporter, known as SGLT1. As the name indicates, this molecule transports both glucose and sodium ions into the cell. Once absorbed into the enterocyte, glucose must be exported from the cell into blood. Sodium is rapidly shuttled out in exchange for potassium by Na+/K+ ATPase pumps on the basolateral membrane, and that process maintains the electrochemical gradient across the epithelium. Glucose, galactose and fructose are transported out of the enterocyte into the interstitium and in turn into the blood through another hexose transporter (called GLUT-2) in the basolateral membrane. These monosaccharides then diffuse down a concentration gradient into capillary blood.
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This question is part of the following fields:
- Gastrointestinal
- Physiology
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Question 39
Correct
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Arterioles stemming from the coronary artery can also empty into the heart directly via the:
Your Answer: Arteriosinusoidal vessels
Explanation:Most of the venous blood returns to the heart via the coronary sinus and the anterior cardiac veins. Apart from these there are other vessels that drain directly into the heart chambers. They include arteriosinusoidal vessels, which connect the arterioles to the heart chambers. The thebesian veins drain the capillaries into the chambers and the arterioluminal vessels drain small arteries directly into the chambers.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 40
Incorrect
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A trauma victim who has been intubated is tachycardic, hypotensive, and has a poor urine output. You feel she is dehydrated and decide to use a central venous catheter to help you manage her. As part of this, you keep an eye on the waveform of central venous pressure (CVP). Which of the following cardiac cycle phases corresponds to the CVP waveform's 'a wave'?
Your Answer: Late systole
Correct Answer: End diastole
Explanation:The pressure measured in the right atrium or superior vena cava is known as central venous pressure (CVP). In a spontaneously breathing subject, the usual CVP value is 0-8 cmH2O (0-6 mmHg). The structure of the CVP waveform is as follows: The CVP’s components are listed in the table below: Component of the waveform The cardiac cycle phase. mechanical event mechanical event Diastole Atrial contraction a wave C wave v wave Early systole The tricuspid valve closes and bulges Late Systole Filling of the atrium with systolic blood x descent y descent Mid systole Relaxation of the atrium Early diastole Filling of the ventricles at an early stage
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 41
Incorrect
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The myocardium is responsible for creating the force with which the atrial and ventricular muscles contract. It is made up of myocytes, which are heart muscle cells. Which of the following statements about cardiac muscle anatomy is correct?
Your Answer: There are usually multiple nuclei within each myocyte
Correct Answer: Cardiac myocytes have intercalated discs
Explanation:Typically, granuloma has Langerhan’s cells (large multinucleated cells ) surrounded by epithelioid cell aggregates, T lymphocytes and fibroblasts. Antigen presenting monocytic cells found in the skin are known as Langerhan’s cells.
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This question is part of the following fields:
- Cell Biology
- Physiology
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Question 42
Incorrect
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Which of the following predominate in the renal medulla?
Your Answer: ACTH secreting cells
Correct Answer: Epinephrine secreting cells
Explanation:Chromaffin cells, also known as pheochromocytes, are cells located in the adrenal medulla which specialize in the synthesis, storage, and secretion of catecholamines: 80% epinephrine and 20% norepinephrine is released into the bloodstream. For this reason, they are considered to be neuroendocrine cells.
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This question is part of the following fields:
- Endocrinology
- Physiology
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Question 43
Correct
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The principle by which the energy of contraction is proportional to the initial length of cardiac muscle fiber is known as:
Your Answer: Starling’s law
Explanation:The Frank starling relationship describes that an increase in the venous return or the end diastolic volume will cause an increase in the stroke volume/ preload and also cardiac output. It stems from the fact that increase venous return will increase the stretch on the ventricular muscle fibers. The sarcomere will stretch a considerable length that is needed for maximum contraction and increased development of tension in the muscle fiber. The greater the venous return the greater the cardiac output. This relation is directly proportional.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 44
Correct
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The motor speech area (Brocas Area) is:
Your Answer: Brodmann area 44
Explanation:A Brodmann area in the brain is defined by cytoarchitecture, histology and organization of cells:Primary Sensory 3,1,2Primary Motor 4Premotor 6Primary Visual 17Primary Auditory 41Brocas 44
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This question is part of the following fields:
- Neurology
- Physiology
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Question 45
Incorrect
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On a mountain the atmospheric pressure is 700 mmHg and the humidity close to zero, the partial pressure of oxygen is:
Your Answer: 110 mmHg
Correct Answer: 147 mmHg
Explanation:Natural air includes approximately 21% of oxygen. If humidity is zero, the partial pressure of oxygen is 700 × 21% = 147 mmHg
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 46
Incorrect
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The complex twisting and folding of peptide chains describes which order of protein structure?
Your Answer: Tertiary structure
Correct Answer: Secondary structure
Explanation:Secondary Structure refers to the coiling or folding of a polypeptide chain that gives the protein its 3-D shape. There are two types of secondary structures: the alpha (α) helix and the beta (β) pleated sheet.
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This question is part of the following fields:
- Metabolism
- Physiology
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Question 47
Correct
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When the heart rate is increased (to pathological levels) which of the following is correct when comparing the duration of diastole to systole?
Your Answer: It is shortened to a greater degree
Explanation:The duration of systole is more fixed than the duration of diastole. When the heart rate increases the timing of the systole remains more or less the same however diastole decreases.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 48
Incorrect
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Where are the cell bodies to the preganglionic neurons located?
Your Answer: Premotor cortex
Correct Answer: Midbrain
Explanation:The cell bodies of the preganglionic neurons are located in the lateral grey column of the spinal cord and in the motor nuclei of the 3rd, 7th, 9th and 10th cranial nerves. These cranial nerves take origin from the midbrain.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 49
Correct
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The conversion of fructose to fructose 1-phosphate is catalysed by:
Your Answer: Fructokinase
Explanation:The first step in the metabolism of fructose is the phosphorylation of fructose to fructose 1-phosphate by fructokinase.
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This question is part of the following fields:
- Metabolism
- Physiology
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Question 50
Incorrect
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Which mechanism of action does Quinolones use?
Your Answer: Inhibit cell wall synthesis
Correct Answer: Inhibit DNA gyrase
Explanation:The quinolones are a family of synthetic broad-spectrum antibiotic drugs. Quinolones exert their antibacterial effect by preventing bacterial DNA from unwinding and duplicating.
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This question is part of the following fields:
- Infectious Diseases
- Physiology
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SESSION STATS - PERFORMANCE PER SPECIALTY
