Mock Exam 03
Final Mock 3
MRCOG Part 1 practice — 109 questions with answers and explanations. Cleaned for readability.
Q1. What type of compound is Histones? - A) Carbohydrate - B) Fatty acid - C) Prostaglandin - D) Protein - E) Steroid
Explanation: Protein Q2. What percentage triiodothyronin (T3) is free? - A) 0.1% - B) 1% - C) 5 % - D) 15% - E) 70%
Explanation: Approximately 80% is bound to TBG, 5% to TTR, and 15% to albumin and lipoproteins. About 0.5% of T3 in the serum is free. It is the free T3 and T4 concentrations in the blood that are responsible for biologic activity. Q3. Which of the following hormones increases the excretion of - A) calcium in Kidney? - B) Insulin - C) Cortisol - D) Calcitonin - E) Parathyroid hormone Antidiuretic hormone
Explanation: PTH also lowers the amount of calcium lost in the urine and stimulates active vitamin D production in the kidneys. Therefore, calcitonin plays a role in maintaining normal blood levels of vitamin D. Calcitonin also regulates the level of calcium and other mineral levels in the kidneys. To this end, this protein prevents the reabsorption of phosphate by the kidney and increases the kidney’s reabsorption of calcium and magnesium, thus leading to increased calcium excretion via the urine. Cortisol indirectly acts on bone by blocking calcium absorption which decreases bone cell growth,The disruption to serum calcium homeostasis increases bone resorption. Q4. Which of the following is the most active form of vitamin D? - A) Ergosterol - B) 7-dehydrocholesterol - C) 25 hydroxycholecalciferol - D) 24,25 dihydroxycholecalciferol - E) 1 alpha 25 hydroxy derivative Calcitriol
Explanation: Vitamin D, as either D3 or D2, does not have significant biological activity. Rather, it must be metabolized within the body to the hormonally-active form known as 1,25 dihydroxycholecalciferol. Q5. Which enzyme in the renal tubular cells are responsible for - A) production of ammonia? - B) Glutaminase - C) Urease - D) Arginase - E) Glutamate dehydrogenase Carbonic anhydrase
Explanation: PDG is the initial enzymatic step in renal ammoniagenesis. It is located in mitochondria and catalyzes the reaction, L-glutamine + H2O → Lglutamate− + NH4+. In the kidney, PDG activity has been localized to the proximal straight and convoluted tubules. Q6. Which substance removed from proinsulin to release insulin into - A) the circulation? - B) Preproinsulin - C) Substance P - D) A peptide - E) B peptide C peptide
Explanation: C-peptide is removed in the Golgi apparatus from proinsulin resulting in the formation of the mature insulin molecule with both alpha and beta chains bound together by disulfide bonds. Q7. What kind of cells secrete Calcitonin hormone? - A) Chief cells - B) Parafollicular cells - C) Oxyphilic cells - D) G cells - E) Follicular cells
Explanation: Parafollicular cells
- Guanylate cyclase receptor
- Nuclear transcription factor
- Tyrosine kinase nuclear receptor
- Ligand-gated ion channel in the cell membrane G protein coupled receptor on the Golgi complex
Q8. Explanation: - A) What is the most common cause of Cushing's syndrome? - B) Administration of synthetic ACTH - C) Paraneoplastic syndrome - D) Pituitary adenoma - E) Iatrogenic steroid administration Adrenal adenoma
Explanation: The most common cause of Cushing's syndrome is the long-term, highdose use of the cortisol-like glucocorticoids. Q9. Which of the following metabolic processes produces the most - A) energy needed for uterine contraction during parturition? - B) Aerobic glycolysis - C) Anaerobic glycolysis - D) Krebs cycle - E) Oxidative phosphorylation Beta oxidation
Explanation: The oxidative pathway covers the largest part of the energy demand of labor, although in the second stage or, in polysystolic labor, the nonoxidative pathway becomes important as well. Glucose is the main maternal energy source, but the rise in ketobodies, even during normal labor, suggests a relative shortage. In the first stage of labor, a combination of a respiratory alkalosis, and to a lesser extent, a metabolic acidosis, result in a rise in the maternal pH. In the second stage of labor, the maternal pH decreases due to an increasing metabolic acidosis. Glucose is also the main fetal energetic fuel. Q10. Which enzyme found in red blood cells that buffers blood CO2 ? - A) Cytochrome-b5 reductase - B) 5-nucleotidase - C) Glucose-6-phosphate dehydrogenase - D) Carbonic anhydrase - E) Pyruvate kinase
Explanation: Carbonic anhydrase
of galactorrhoea. She is otherwise healthy and is not taking any medications. Nothing abnormal is found in the examination. Her hormonal profile was a follows : FSH 8.7 iU/l LH 4.5 iU/l Oestradiol 100 pmol/l Prolactin 700 mU/l TSH 15 mU/l Free T4 9 iU/l * What is the most likely cause ? * Prolactinoma * Non-functioning pituitary tumour * Addison's disease * Hypothyroidism - E) Hyperthyroidism
Explanation: Hypothyroidism
loss in the previous four months. She has been amenorrheic for some months. Her examination is completely normal. Her urine pregnancy test is negative. Her laboratory results shows Luteinizing hormone 0.3 mIU/l Follicle-stimulating hormone 0.2 iu/l Prolactin 400 mU/l Thyroid stimulating hormone 1.5 mIU/L Total T4 200 nmol/L Total T3 2 nmol/L * What is the most likely diagnosis? * Hypothalamic dysfunction * Pituitary adenoma * Ovarian dysgenesis * Polycystic ovary syndrome - E) Hyperthyroidism
Explanation: Hypothalamic dysfunction Q11. Which process occurs in the mitochondria where uses electrons - A) transport to generate adenosine triphosphate (ATP)? - B) Krebs cycle - C) Cori's cycle - D) Glycolysis - E) Substrate level phosphorylation Oxidative phosphorylation
Explanation: Oxidative phosphorylation
- Arachidonic acids
- Oleic acids
- Linoleic acids
- Steroids
- E) Cholesterols
Explanation: Arachidonic acids
with abdominal discomfort, 2+ proteinuria and a blood pressure of 140/90 mmHg. She has blood tests in accordance with the NICE guideline for the management of hypertension in pregnancy. The midwife asks you to review the following blood results. What do these results suggest? Urea 2.8 mmol/l Creatinine 67 micromol/l Sodium 138 mmol/l Potassium 4.2 mmol/l Urate 0.37 mmol/l Albumin 32 g/l Alkaline phosphatase 198 iu/l Alanine transferase 33 iu/l * Bilirubin 5 mmol/l * Acute fatty liver of pregnancy * Cholestasis of pregnancy * HELLP syndrome * Normal blood results for 36 weeks of pregnancy - E) Cholecystitis
Explanation: Normal blood results for 36 weeks of pregnancy
the past few months she has been feeling generally tired. Prior to this she had a regular 30 day cycle. Her urine pregnancy test is negative. Pelvic examination is normal and routine bloods are ordered: Luteinizing hormone 33 mIU/l Follicle-stimulating hormone 51 iu/l Prolactin 300 mU/l Thyroid stimulating hormone 3.1 mIU/L (0.2-5.5) Total T4 100 nmol/L (50-500) Total T3 1.5 nmol/l (0.9-2.8) Oestradiol 70 pmol/l (100-500) * What is the most likely diagnosis? * Hypothalamic dysfunction * Gonadotropin-producing pituitary adenoma * Premature ovarian failure * Polycystic ovary syndrome - E) Primary hypothyroidism
Explanation: When a woman's FSH blood level is consistently elevated to 30 mIU/mL or higher, and she has not had a menstrual period for a year, it is generally accepted that she has reached menopause.
past five years. In this patient, which one of the following hormones would * decrease the appetite as levels increase? * Leptin * Thyroxine * Ghrelin * Adiponectin - E) Insulin
Explanation: Leptin
- Cytosol
- Mitochondrial matrix
- Mitochondrial cristae
- Rough endoplasmic reticulum
- E) Smooth endoplasmic reticulum
Explanation: Cytosol Q12. What type of acid–base disturbance result in a case of Conn's - A) syndrome? - B) Metabolic acidosis - C) Metabolic alkalosis - D) Respiratory acidosis - E) Respiratory alkalosis No effect
Explanation: Metabolic alkalosis Q13. What kind of cells produces parathyroid hormone (PTH)? - A) Chief cells - B) Parathynotic cells - C) Oxyphilic cells - D) C cells - E) Follicular cells
Explanation: Chief cells Q14. What is the second common cause of congenital adrenal - A) hyperplasia (CAH)? - B) 17-hydroxylase deficiency - C) 21-hydroxylase deficiency - D) 11-Beta hydroxylase deficiency - E) 3 Beta- hydroxysteroid dehydrogenase deficiency 17 Beta-hydroxysteroid dehydrogenase deficiency
Explanation: 11-Beta hydroxylase deficiency Q15. Gonadotropin Releasing Hormone (GnRH) is what type of - A) Biochemical? - B) Tripeptide - C) Octapeptide - D) Nanopeptide - E) Decapeptide Polypeptide
Explanation: Decapeptide Q16. What type of compound is thyroid releasing hormone (TRH)? - A) Carbohydrate - B) Protein - C) Glycoprotein - D) Polypepetide - E) Steroid
Explanation: Polypepetide
- Sex hormone-binding globulin (SHBG)
- Corticosteroid-binding globulin (CBG)
- Thyroid-binding globulin (TBG)
- Albumin
- E) Pre-albumin (transthyretin)
Explanation: Testosterone and estradiol circulate in the bloodstream, loosely bound mostly to serum albumin (~54%), and to a lesser extent bound tightly to SHBG (~44%). Only a very small fraction of about 1 to 2% is unbound, or "free," CORTISOL 70% is bound to corticosteroid binding globulin (transcortin), 22% of cortisol is bound to albumin, 8% free cortisol. ALDOSTERONE 60% of aldosterone is bound to albumin, 10 % is bound to transcortin Q17. What is the most common cause of A healthy 34-year-old woman - A) had a total abdominal hysterectomy for cervical disease. - B) Routine urea and electrolytes are measured one day after surgery and - C) are as follows : - D) Sodium 121 (reference range 135-145 mmol/l) - E) Potassium 4.3 (reference range 3.5-5.0 mmol/l) Urea 2.8 (reference range 2.5-6.7 mmol/l) Creatinine 74 (reference range 70-150 micromol/l) What is the most likely cause to explain the blood test results? * Excessive intravenous dextrose * Nephrogenic diabetes insipidus * Primary aldosteronism * Undiagnosed diabetes mellitus Ureteric damage
Explanation: Post-Operative Hyponatraemia. Fluid retention is seen as part of stress response to surgery. There is an increase in hypothalamic- pituitary hormone secretion, resulting in increased cortisol and ADH release. The resulting free water reabsorption in excess of sodium results in a hyponatraemia. In addition, surgical patients receive significant volumes of intravenous fluid during the perioperative period. If the fluid used is dextrose solution (especially if excessive or prolonged use), this will cause a dilutional effect to the body’s serum sodium levels.
- which of the following hormones?
- Anti mullerian hormone
- Cortisol
- Follicle-stimulating hormone
- Growth hormone
- E) Prolactin
Explanation: Growth hormone
with increased facial hair growth and weight gain since she quit smoking. Her urine pregnancy test is negative. Her serum hormonal levels are as follows: FSH 5 lU/L LH 15 IU/L Prolactin 300 mmol/l Serum oestradiol 350 pmol/L * What is the most likely diagnosis? * Gonadotropin-producing pituitary adenoma * Polycystic ovarian disease * Congenital adrenal hyperplasia * Premature ovarian failure - E) Ovarian neoplasm
Explanation: Polycystic ovarian disease
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- Adrenal capsule
- Zona reticularis
- Zona glomerulosa
- Zona fasciculata
- E) Adrenal medulla
Explanation: Zona reticularis
never had a menstrual period. On examination she is short, wide spaced nipples, webbed neck with coarctation of aorta. * What is the most likely diagnosis? * Mullerian agenesis * 5-alpha reductase deficiency * Turner syndrome * Anorexia nervosa - E) Primary hypothyroidism
Explanation: Turner syndrome Q18. Glucagon works by which of the following mechanisms to reverse - A) the hypoglycemia? - B) Glycolysis - C) Glycogenesis - D) Gluconeogenesis - E) Krebs cycle Oxidative phosphorylation
Explanation: Glucagon generally elevates the concentration of glucose in the blood by promoting gluconeogenesis and glycogenolysis.
breathlessness, tachycardia and menstrual irregularity. Her Investigations revealed: Serum hCG negative Serum T4 178 mmol/l Serum TSH 0.05 mU/L Prolactin 400 mmol/l * What is the most likely diagnosis? * Primary hypothyroidism * Graves' disease * Hashimoto's thyroiditis * Multi-nodular goitre - E) DeQuervain's thyroiditis
Explanation: Graves' disease Q19. Glucocorticoids are secreted from which region of the adrenal - A) gland? - B) Adrenal capsule - C) Zona reticularis - D) Zona glomerulosa - E) Zona fasciculata Adrenal medulla
Explanation: Zona fasciculata
- glycoprotein hormones?
- ADH, oxytocin and FSH
- FSH, TSH and growth hormone
- HCG, ADH and FSH
- HCG, FSH and TSH
- E) TSH, growth hormone and HCG
Explanation: HCG, FSH and TSH
- 18
- 19
- 20
- 21
- E) 22
Explanation: 19
- of
- Xanthine oxidase
- Glutaminase
- Nucleoside phosphorylase
- Urease
- E) Uricase
Explanation: Xanthine oxidase Q20. Which organ is the principal site of urea synthesis via the urea - A) cycle? - B) Liver - C) Kidneys - D) GIT - E) Lungs Bone marrow
Explanation: The liver is the only site where urea is synthesized and ultimately excreted by the kidneys.
- secondary hyperparathyroidism. It is usually associated with
- Parathyroid gland tumour
- Chronic liver disease
- Thyroid carcinoma
- Chronic kidney disease
- E) Syndrome of inappropriate antidiuretic hormone (SIADH)
Explanation: Type explanation here... Q21. What is the most common cause of Cushing's syndrome? - A) Pituitary adenoma - B) Adrenal adenoma - C) Adrenal carcinoma - D) Adrenal hyperplasia - E) Iatrogenic steroid administration
Explanation: Iatrogenic steroid administration Q22. What is the most common cause of hyperprolactinemia? - A) Macroprolactinoma - B) Microprolactinoma - C) Primary hypothyroidism - D) Chronic renal failure - E) Pituitary stalk interruption syndrome (PSIS)
Explanation: Primary hypothyroidism
- Guanylate cyclase receptor
- Nuclear transcription factor
- Tyrosine kinase nuclear receptor
- Ligand-gated ion channel in the cell membrane
- E) G protein coupled receptor on the Golgi complex
Explanation: Nuclear transcription factor
- When is the highest peak of growth hormone release?
- Early morning
- After exercise
- Afternoon
- Early sleep
- E) Deep sleep
Explanation: Deep sleep
- Calcidiol
- Ergosterol
- 7-dehydrocholesterol
- 1, 25-Dihydroxycholecalciferol
- E) 24, 25-Dihydroxycholecalciferol
Explanation: Vitamin D, as either D3 or D2, does not have significant biological activity. Rather, it must be metabolized within the body to the hormonally-active form known as 1,25 dihydroxycholecalciferol. Q23. Which type of pituitary gland tumors increase growth hormone - A) secretion lead to acromegaly? - B) Adenoma - C) Glioma - D) Fibroma - E) Sarcoma Schwannoma
Explanation: Adenoma Q24. Which type of cell junctions helps in transmission of small - A) molecules or ions from one cell to another? - B) Adherens junctions - C) Desmosomes - D) Diffusion spheres - E) Tight junctions Gap junctions
Explanation: Gap junctions provide metabolic and electrical coupling between cells. For example, cardiac tissue has extensive gap junctions, and the rapid movement of ions through these junctions helps the tissue beat in rhythm. Q25. Which neurotransmitter is secreted onto the adrenal medulla? - A) Acetylcholine - B) Norepinephrine - C) Epinephrine - D) Dopamine - E) Serotonin
Explanation: The adrenal medulla is the central core of the adrenal gland. The neurotransmitter released from the myelinated presympathetic nerve endings is Acetylcholine, so this is the main stimulus for the release of hormones from the adrenal medulla. Epinephrine is the principal hormone secreted by the adrenal medulla, although it also releases some norepinephrine. The rate of secretion of catecholamines by the adrenal medulla is largely regulated by the same mechanisms that control sympathetic nervous activity. Q26. Glucose-6-phosphatase deficiency is a common metabolic - A) disease in Africa. - B) What is the function of the enzyme glucose-6-phosphatase in - C) carbohydrate metabolism? - D) Adds glucose to glycogen ends - E) Adds phosphate to glucose * Production of ATP in aerobic and anaerobic oxidation * Production of NADPH in red blood cells Converts glucose-6-phosphate to Glucose
Explanation: Glucose 6-phosphatase is an enzyme that hydrolyzes glucose 6- phosphate, resulting in the creation of a phosphate group and free glucose.
- converted to glucose by the process of
- Rapport luebering cycle
- Glucose alanine cycle
- Cori's cycle
- Citric acid cycle
- E) Glycolysis
Explanation: Cori's cycle Q27. Which cell type, in the islets of Langerhans, secretes glucagon? - A) Alpha cells - B) Beta cells - C) Delta cells - D) Epsilon cells - E) PP cells
Explanation: Alpha cells
steroidogenesis in their proper sequence. * Which substance is indicated by letter 'X' in the above diagram? * Estrone * Testosterone * Dihydrotestosterone * Androstenedione - E) Dehydroepiandrosterone
Explanation: It also came the other way asking about the compound formed from DHEA , very important pathway
luteinizing hormone (LH) levels and high estradiol levels. * What is the most likely cause of this? * Hypogonadotrophic hypogonadism * Ovarian failure * Midcycle LH surge * Polycystic ovary syndrome - E) Weight-related amenorrhoea
Explanation: PCOS should be diagnosed according to the Rotterdam consensus criteria. Estrogen secretion in PCOS women is characterized by chronic secretion without the cyclic pattern that accompanies an ovulatory cycle. Serum estradiol (E2) levels may vary in PCOS but are usually in the mid-follicular phase range of 60–90 pg/mL In a normal menstrual cycle, estradiol levels fluctuate as follows: <50 pg/ml during menstrual periods. 200 pg/ml (maximum) during follicular development. 400 pg/ml (maximum) just before ovulation.
amenorrhea. In addition, her periods are irregular of two years' duration. She is overweight and complains of increasing lethargy. Nothing abnormal is found on examination. Her hormone profile was as follows: βhCG < 5 IU/L LH = 4 IU/L FSH = 3.5 IU/L Prolactin = 400 mIU/L TSH = 7 mIU/L Free T4 = 9 IU/L * What is the most likely diagnosis? * Hyperthyroidism * Hypothyroidism * Normal pregnancy * Polycystic ovary syndrome - E) Kallmann syndrome
Explanation: Hypothyroidism
- Para ventricular nucleus of hypothalamus
- Acidophillic cells of anterior pituitary
- Neuroendocrine cells of posterior pituitary
- All of above
- E) None of above
Explanation: Para ventricular nucleus of hypothalamus
- value of calcium and phosphate
- Inc Ca. Dec phosphate
- Dec Ca. Inc phosphate
- Inc Ca. Inc phosphate
- Dec Ca. Dec phosphate
- E) None of above
Explanation: Inc Ca. Dec phosphate Q28. Order the following hormones according to their potency from - A) maximum to minimum - B) DHT...Androstenedione...DHEA ...Testosterone - C) DHT...Testosterone...Androstenedione...DHEA - D) Testosterone. ..DHT...Androstenedione...DHEA - E) All of above None of above
Explanation: DHT...Testosterone....Androstenedione...DHEA Q29. What is the most abundant carbohydrate in the breast milk? - A) Caesin - B) Galactose - C) Glucose - D) Lactose - E) Sucrose
Explanation: Lactose
L arginine L aspartate L lysine L guanine
Explanation: Nitric oxide (NO), synthesized from the amino acid l-arginine by NO synthases, is a unique type of transmitter in the nervous system.
Fsh 4 Lh 3 Prolactin normal Tsh normal * What is your Diagnosis? * Hypothalamic amenorrhea * Premature ovarian failure * Hyperthyroidism * All of above - E) None of above
Explanation: Hypothalamic amenorrhea
Q30. Active form of Vit-D is produced in which organ? - A) Skin - B) Liver - C) Lungs - D) Kidney - E) Adrenal glands
Explanation: It is activated by two protein enzyme hydroxylation steps, the first in the liver and the second in the kidneys. Cholecalciferol is converted in the liver to calcifediol (25- hydroxycholecalciferol); ergocalciferol is converted to 25- hydroxyergocalciferol. These two vitamin D metabolites (called 25- hydroxyvitamin D or 25(OH)D are measured in serum to determine a person's vitamin D status. Calcifediol is further hydroxylated by the
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Q31. 41 years old women presents to clinic complaining of - A) galactorrhea. - B) Labs show: FSH, LH and TSH raised. - C) Hyperthyroidism - D) Hypothyroidism - E) Premature ovarian insufficiency * PCOS Hypothalamic Dysfunction
Explanation: Premature ovarian insufficiency
Q32. A 30 years old women who regularly takes insulin for diabetes. - A) Presents with lethargy and loss of weight, TSH is low & Total T3 high? - B) Graves disease - C) Hashimotos thyroiditis - D) Toxic nodule - E) Ketoacidosis Hypothyroidism
Explanation: Graves disease - A) and should be taken from dietry intake ? * α-Linoliec acid * Ecosapentoenoic acid * Arginine * Arachidonic acid - E) Histidine
Explanation: Omega-3 fatty acids are found in foods, such as fish and flaxseed, and in dietary supplements, such as fish oil. The three main omega-3 fatty acids are alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). * Platelets * Liver * Macrophages * Kidney - E) Mast cells
Explanation: Thromboxane A2 (TXA2) is a potent vasoconstrictor produced by endothelial cells, activated platelets and macrophages. endothelial cells produce prostacyclin, a potent vasodilator and inhibitor of platelet aggregation.
Q33. Regarding Insulin, it gets activated by removing? - A) A-peptide - B) B-peptide - C) C-peptide - D) D-peptide - E) E-peptide
Explanation: C-peptide
Q34. Conversion of Fe3+ to Fe2+ in gut require which of the following - A) vitamins? - B) Vit A - C) Vit B6 - D) Vit B12 - E) Vit C Vit K
Explanation: Vit C * Bicarbonate * Magnisium * Phosphate * Chloride - E) Sodium
Explanation: Phosphate * Liver * Kidney * Lungs * Adrenals - E) Red blood cell
Explanation: Liver is production site Kidney is excretion site
Q35. Vitamin A has 2 diet sources. Plant source is carotene and the - A) animal source is - B) Cryptoxantene - C) Gamma carotene - D) Isotretinoin - E) Retinol Retinyl palmitate
Explanation: Vitamin A is found as retinol, the 'active' form of vitamin A. Liver, including fish liver, is a very good source.
Q36. Young female 25 years old patient 7 weeks pregnant with - A) complaint of tiredness - B) TSH 8.5 ( 0.5-5 mlU/L ) - C) T4 14 ( 5-12 ug/dl ) - D) T3 5.4 ( 0.9-2.8 nmol/l ) - E) Euthyroid * Primary Hypothyroidism * Secondary Hypothyroidism * Subclinical Hypothyroidism Hyperthyroidism
- Histidine
- Glycine
- Arginine
- Tyrosine Tryptophan
Explanation: Tryptophan * Cytoplasm * Mitochondria * Plasma membrane * Rough ER - E) Smooth ER
Explanation: Mitochondria
Q37. Rate limiting step in the synthesis of catecholamines? - A) Acetylcholine esterase - B) DOPA decarboxylase - C) Dopamine B hydroxylase - D) Tyrosine hydroxylase - E) Phenyl N methyl transferase
Explanation: Tyrosine hydroxylase
Q38. Rate limiting step of glycolysis? - A) Phosphofructokinase - B) Fructose 1, 6 bisphosphatase - C) Fructose 1, phosphatase - D) Fructokinase - E) Citrate dehydrogenase
Explanation: Phosphofructokinase
Q39. Rate limiting step in Krebs cycle ? - A) Citrate dehydrogenase - B) Fructose 1, 6 bisphosphatase - C) Phosphofructokinase - D) Isocitrate dehydrogenase - E) Fructokinase
Explanation: Isocitrate dehydrogenase (IDH) is an oxidoreductase that catalyzes an oxidation reduction in which isocitrate is converted to alpha-ketoglutarate and CO2. It is the first of four oxidative steps within the TCA cycle and is the key rate-limiting step of the TCA cycle. - A) control? * Maternal decidua * Anterior pituitary * Hypothalamus * Posterior pituitary - E) Warthon's jelly
Explanation: It is well-known that dopamine constitutively inhibits prolactin (PRL) secretion via the dopamine receptor 2 (DR2D) Dopamine receptors are expressed in the central nervous system, specifically in the hippocampal dentate gyrus and subventricular zone. Dopamine receptors are also expressed in the periphery, more prominently in kidney and vasculature. * Vitamin B1 * Vitamin B2 * Vitamin B3 * Vitamin B6 - E) Vitamin B12
Explanation: Vitamin B1 * Antioxidant * Boost immune system * Collagen formation * Helps in wound healing - E) None of above
Explanation: All other options are also important functions of vitamin C
Q40. Cells in the body produce hormones among them how many are - A) lactotrophs? - B) 1-5% - C) 10-15% - D) 15-25% - E) 25-30% 40-50%
Explanation: They are located predominantly in the lateral wings of the pituitary gland. 10-15% of pituitary cells are lactotrophs, or the cells producing prolactin.
Q41. Hashimotos thyroiditis - A) Hyperthyroidism - B) Toxic nodule - C) Ketoacidosis - D) Hypothyroidism - E) None of above
Explanation: Hypothyroidism
Q42. In which part of the cell does glycolysis take place? - A) Cytosol - B) Mitochondrial matrix - C) Mitochondrial cristae - D) Rough endoplasmic reticulum - E) Smooth endoplasmic reticulum
Explanation: Cytosol
Q43. 32-year-old female presents with a two month history of - A) breathlessness, tachycardia and menstrual irregularity. Her Investigations - B) revealed: - C) Serum hCG negative - D) Serum T4 178 mmol/l - E) Serum TSH 0.05 mU/L Prolactin 400 mmol/l * What is the most likely diagnosis? * Primary hypothyroidism * Graves' disease * Hashimoto's thyroiditis * Multi-nodular goitre DeQuervain's thyroiditis
Explanation: In patients with primary hypothyroidism, increased levels of TRH can cause to rise prolactin levels and these patients may have galactorrhea and can be presented with pituitary hyperplasia. Hyperprolactinemia is also more frequent in hyperthyroid females. Serum prolactin level can be increased in hyperthyroidism. De Quervain's (subacute) thyroiditis is a painful swelling of the thyroid gland thought to be triggered by a viral infection, such as mumps or flu. It's most commonly seen in women aged 20 to 50. It usually causes high temperature and pain in the neck, jaw or ear.
Q44. No of carbons in Estrogen? - A) 18 - B) 19 - C) 20 - D) 21 - E) 22
Explanation: According to the number of carbon atoms, sex steroids are divided into three groups: progestins, characterized by 21-carbon atoms; androgens, characterized by 19-carbon atoms; estrogens, characterized by 18- carbon atoms. * Diabetes Mellitus * Polycystic Ovarian Syndrome * Premature Ovarian Failure * Hypothyroidism - E) Hyperprolactenimia
Explanation: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder amongst women of reproductive age, PCOS affects as many as 10% of reproductive-age women when using the NIH criteria for diagnosis, and up to 18% of reproductive-age women are diagnosed with PCOS as per the Rotterdam criteria.
Q45. Vitamin E toxicity - A) Dementia - B) Renal failure - C) Cardiomyopathy - D) Haemorrhage - E) Lung fibrosis
Explanation: Relatively large amounts of vitamin E usually cause no harm but occasionally muscle weakness, fatigue, nausea, and diarrhea occur. The most significant risk is bleeding, mainly with doses > 1000 mg a day.
Q46. The effects of prostaglandins are mediated by - A) Autocrine - B) Paracrine - C) Endocrine - D) Eccrine - E) Exocrine
Explanation: Prostaglandins are found in most tissues and organs. They are produced by almost all nucleated cells. They are autocrine and paracrine lipid mediators that act upon platelets, endothelium, uterine and mast cells. They are synthesized in the cell from the fatty acid arachidonic acid.
Q47. Precursor of testosterone in theca cell - A) Androstenedione - B) DHT - C) Estriol - D) Estradiol - E) Cholesterol
Explanation: Theca interna cells express receptors for luteinizing hormone (LH) to produce androstenedione, which via a few steps, gives the granulosa the precursor for estrogen manufacturing. After rupture of the mature ovarian follicle, the theca interna cells differentiate into the theca lutein cells of the corpus luteum. Theca lutein cells secrete androgens and progesterone. Theca lutein cells are also known as small luteal cells.
Q48. Primary amenorrhea with absent uterus, vagina ends in a blind - A) pouch, normal breasts and scant pubic hair is seen in - B) Klinefelter Syndrome - C) Mayer Rokitanski Kusher Hauser Syndrome - D) Turner's Syndrome - E) Androgen Insensitivity Syndrome Noonan Syndrome
Explanation: Androgen Insensitivity Syndrome
Q49. The vitamin causing Pellagra - A) Thiamine - B) Pyridoxine - C) Cobalamin - D) Niacin - E) Ascorbic acid
Explanation: Niacin
Q50. Angiotensin 1 to angiotensin 2 conversion occur in? - A) Brain - B) Lung - C) GIT - D) Kidney - E) None of above
Explanation: Angiotensin I is produced by the action of renin (an enzyme produced by the kidneys) on a protein called angiotensinogen, which is formed by the liver. Angiotensin I is transformed into angiotensin II in the blood by the action of angiotensin-converting enzyme (ACE). It is located mainly in the capillaries of the lungs but can also be found in endothelial and kidney epithelial cells. - A) normal. * Anabolic steroids * Congenital absence of Vas * Testicular failure * Seminoma - E) Vasectomy
Explanation: Normal testosterone, normal LH, and elevated FSH levels in an azoospermic or severely oligozoospermic man are suggestive of primary spermatogenic failure. These men should undergo measurement of testicular volume, karyotyping.
Q51. TRH is - A) Tripeptide - B) Glycoprotein - C) Polysaccharide - D) Disaccharide - E) None of above
Explanation: Tripeptide
Q52. Delta cells of pancreas secrets - A) Somatostatin - B) Glucagon - C) Insulin - D) Pancreatic polypeptide - E) Cholecystokinin
Explanation: Somatostatin
(Page 4) 94. 95. 96. 97. 98. 99. 100. 101. 102. 103. 104. 105. 106. 107. 108. 109. - A) Logout * Due to increased progesterone hormone * Due to increased unopposed estrogen * Due to increased insulin level * Due to increased androgen hormone - E) None of above
Explanation: Due to increased unopposed estrogen
Q53. PKU there is deficiency of enzyme known as hydroxylase. - A) This enzyme catalyze the reaction and converting phenylalanine to - B) Tryptophan - C) Trypsinogen - D) Tyrosine - E) Tyronine None of above
Explanation: Tyrosine
Q54. NO is derived from - A) Arginine - B) L-Arginine - C) L-Alanine - D) D-Alanine - E) None of above
Explanation: L-Arginine
Q55. Rate limiting step in urea synthesis - A) Acetylglutamate dehydrogenase - B) Acetylglutamate oxygenase - C) N Acetylglutamate dehydrogenase - D) N Acetylglutamate oxygenase - E) None of above
Explanation: N Acetylglutamate dehydrogenase
Q56. Important function of glucagon - A) Glycolysis - B) Gluconeogenesis - C) Beta oxidation - D) Krebs cycle - E) Urea cycle
Explanation: Gluconeogenesis
Q57. Throid profile in pregnancy is checked by - A) Triiodothyronine - B) TSH - C) Thyroid binding globulin - D) All of above - E) None of above
Explanation: TSH - A) structure? * Kidney * Liver * Pancreas * Duedenum - E) Gall bladder
Explanation: GnRH and its receptor have been found to be synthesized in a many of tissues outside of their classical sites of production, such as pituitary, ovary, endometrium and placenta, breast tissue and mammary glands, liver, heart, skeletal muscles, kidney, spleen, lymphocytes, and T cell.
Q58. Integrin - A) Endocrine - B) Paracrine - C) Autocrine - D) All of above - E) None of above
Explanation: Paracrine
Q59. After protein rich meal - A) insulin dec. glucagon inc - B) insulin inc. glucagon dec - C) insulin and glucagon inc - D) insulin and glucagon dec - E) None of above
Explanation: High protein diet is accompanied by increased stimulation of glucagon and insulin within the endocrine pancreas, high glycogen turnover and stimulation of gluconeogenesis.
Q60. Alkaptonuria (AKU) is a disorder of tyrosine/protein metabolism - A) leading to accumulation of homogentisic acid, What vitamin is necessary - B) for those patients? - C) Vit A - D) Vit C - E) Vit D * Vit E Vit K
Explanation: Vitamin C, as much as 1 g/d, is recommended for older children and adults. The mild antioxidant nature of ascorbic acid helps to retard the process of conversion of homogentisate to the polymeric material that is deposited in cartilaginous tissues.
Q61. Enzyme rich cellular organelle with external membrane and - A) internal membrane with folds - B) SER - C) RER - D) Mitochondria - E) Nucleus Chromosome
Explanation: Mitochondria
Q62. Junctions in uterine smooth muscle that aid contractions - A) Desmosomes - B) Gap junction - C) Tight junction - D) Non junction - E) None of above
Explanation: Gap junction
Q63. LH half life - A) 5 min - B) 20 min - C) 30 min - D) 60 min - E) 90 min
Explanation: The biologic half-life of LH is 20 minutes, shorter than that of FSH (3–4 hours) and hCG (24 hours).
Q64. Homocystinuria due to which vitamin deficiency? - A) Vit B1 - B) Vit B2 - C) Vit B3 - D) Vit B5 - E) Vit B6
Explanation: Classic homocystinuria is caused by deficiency of cystathionine βsynthase (CBS), a pyridoxine (vitamin B6) dependent enzyme.
Q65. Patient admitted for nausea and vomiting which vitamin is needed - A) in addition to her treatment ? - B) Riboflavin - C) Niacin - D) Ascorbic acid - E) Thiamine Folic acid
Explanation: Thiamine * Riboflavin * Niacin * Ascorbic acid * Thiamine - E) Folic acid
Explanation: Folic acid
Q66. Source of Vit k 1 - A) Milk - B) Egg - C) Oily fish - D) Green leafy vegetables - E) Raw meat
Explanation: Green leafy vegetables