MCQ POOL 2019

Q1. A 34-year-old man comes to the emergency with a headache and blurred vision. He complains
that his wedding ring no longer fits him and his favourite hat does not fits his head. His wife feels that
his nose has become wider. He was diagnosed with Acromegaly. Which of the following metabolic
effects would you epect in this patient:

a) Decreased protein synthesis

b) Inhibition of gluconeogenesis
c) Inhibition of lipolysis
d) Increased protein synthesis
e) Increased cholesterol synthesis

Q2. A 75-year-old woman with osteoporosis complains of severe back pain. Her MRI scan confirms a
compressing fracture of L3 vertebra. The attending physician begins treating the patient with
morphine for pain control. Morphine is an analgesic that work similarly to which of the following
endogenously produced substance:

a) ACTH
b) POMC
c) Oxytocin
d) Endorphin
e) Lipotropin

Q3 A 56-year-old man with 30 year history of 5, 6 packs/day of cigarette smoking, is recently found to
have a large mass in the lungs, likely a tumour. His initial blood lab shows decreased serum Na of
127mMol/L and decreased urine osmolality. He is likely having which of the following endocrine
abnormality along the lung tumour:

a) Cushing’s disease
b) Cushing’s syndrome
c) Acromegaly
d) Syndrome of inappropriate secretion of ADH
e) Prolactinoma

Q4. Pheochromocytomas are tumours of adrenal medulla characterized by elevated urinary ecretion
of :

a) Vinylmandellic acid
b) Dopamine
c) Tyrosine
d) Serotonin
e) Phenylalanine

Q5. Hyperglycemic effect of glucagon is mainly due to:

a) Decreased glycolysis
b) Suppressed lipolysis.
c) Glycogenolysis in liver
 d) Glycogenolysis in muscles
e) Reduced protein synthesis

Q6. Which of the following statement is correct:

a) Insulin suppresses the activity of glycogen synthase

b) Insulin helps in the glucose uptake by brain
c) “Pre-diabetes” is a condition characterized by an increased risk for the future development
of Type-2 diabetes
d) The rise in insulin concentration after meals remains normal in Type-1 diabetes
e) Insulin actions mediate through cAMP

Q6. Insulin deficiency is associated with:

a) Reduced lipolysis
b) Increased glycolysis
c) Increased ketogenesis
d) Reduced gluconeogenesis
e) Increased glycogenesis

Q7. Tetany can occur:

a) In primary hyperparathyroidism
b) In secondary hyperparathyroidism
c) In idiopathic hypoparathyroidism
d) After accidental removal of parathyroid glands
e) In hypothyroidism

Q8. A 10-year-old boy is being evaluated for abnormal growth. His mother says he is much taller than
children of his ageand seems to sweat a lot. Physical eamination shows long extremities. Both
parents are of average height and built. A thyroid function test shows normal serumTSH. Which of
the following is the most likely cause of this patients condition:

a) Defective growth hormone receptors

b) Excessive free thyroxine levels
c) Increased release of IGF-1 from the hypothalamus
d) Increased release of IGF-1 from liver
e) Increased release of insulin from pancreas

Q9. The biological function of GnRH is:

a) Release og ACTH
b) Inhibition of prolactin release
c) Release of LH and FSH
d) Inhibition of GH secretion
e) Inactivation of insulin

Q10. A major structural difference between estrogens and androgens is the fact that:
 a) The androgens are usually C21 steroids.
b) The estrogens are usually digitonin-precipitable.
c) The androgens have an aromatic ring
d) The estrogens have an aromatic ring
e) Androgens mediate through cAMP

Q11. The hormone measured in blood for confirmation of pregnancy is:

a) Anterior pituitary luteinizing hormone

b) Dehydro-epi-andro-stenedione
c) Progesterone
d) Relaxin
e) Human Chorionic gonadotropin

Q12. Young women are protected against myocardial infarction because of the activity of:

a) Estrogens
b) Progesterons
c) Growth hormone
d) Oxytocin
e) Human chorionic gonadotropin

Q13. Testosterone in blood is transported by:

a) Transcortin
b) Testosterone binding globulin
c) Testosterone estrogen binding globulin
d) Albumin
e) High density lipoprotein (HDL)

Q14. Thiocynates and perchlorates interfere with:

a) Iodination of tyrosine
b) Trapping of iodine by thyroid
c) Release of T3
d) Release of T4
e) Degradation of Tgb

Q15. Which of the following hormones act by inositol 1,4,-triphosphate (IP3)-Ca⁺⁺ mechanism of
action:

a) ,2-Dihydroxycholecalciferol
b) Progesterone
c) Insulin
d) Parathyroid hormone
e) Gonadotropin-releasing hormone (GnRH)

Q16. The glycoprotein group of hormones from anterior pituitary comprise of the following :
 a) Oxytocin, Anti-diuretic hormone
b) LH, FSH, TSH
c) GH, Prolactin
d) ACTH, Lipotropic hormone, endorphins
e) POMC group of hormones

Q17 Excessive production of ACTH by pituitary or ectopic secretion from a tumour results in:

a) Conn’s disease
b) Diabetes mellitus
c) Diabetes insipidus
d) Acromegaly
e) Cushing’s disease

Q18. cAMP activates which of the following enzymes:

a) Adenylyl cyclase
b) Tyrosine kinase
c) Phospholipase C
d) Phosphodiesterase
e) Protein kinase A

Q19. A dietary deficiency of Iodine would do which of the following effect:

a) Directly affect the synthesis of thyroglobulin

b) Result in increased secretion of TSH
c) Result in the decreased production of thyrotropin releasing hormone
d) Result in increased BMR
e) Raise the blood pressure and heart rate

20. Which of the following molecule acts to increase the release of Ca⁺⁺ from the endoplasmic
reticulum:

a) Diacylgycerol (DAG)
b) Inositol triphosphate (IP3)
c) Parathyroid hormone
d) Calcitonin
e) 1,25-dihydroxycholecalciferol (D3)

Q21. Which of the following hormone stimulate the synthesis of milk protein:

a) Luteinizing hormone
b) Prolactin
c) Thyroid stimulating hormone
d) Growth hormone
e) Follicle stimulating hormone

Q22. Release of which of the following is inhibited by thyroxine:

 a) Luteinizing hormone
b) Prolactin
c) Thyroid stimulating hormone
d) Growth hormone
e) Follicle stimulating hormone

Q23. Which of the following hormone promotes ‘Hypoglycemia” :

a) Epinephrine
b) Norepinephrine
c) Growth hormone
d) Glucagon
e) Insulin

Q24 Increased reabsorption of water from kidney is the major consequence of the following
hormone :

a) Cortisol
b) Insulin
c) Vasopressin
d) Glucagon
e) Aldosterone

Q25. Lack of the glucocorticoids and mineralocorticoids might be a result of which of the following
defect in adrenal cortex:

a) Esterone deficiency
b) Testosterone deficiency
c) 17αOH progesterone deficiency
d) Androstenedione deficiency
e) C21 hydroxylase deficiency

Q26. Which of the following hormone can cause “ Hyperglycemia” without known effects on
glycogen or gluconeogenesis :

a) Thyroxine
b) Epinephrine
c) Norepinephrine
d) Glucocorticoids
e) Glucagon

Q28. Which of the following statement best define insulin :

a) Its action is antagonist to glucagon

b) It is a small peptide composed of a single chain bridged by didulfide groups
c) It does not have a prohormone
d) It promotes glucose absorption from the intestine
e) It has a direct role in the uptake of glucose in nerve and RBC
Q29. Which of the following is noted in Cushing’s syndrome :

a) Decreased production of epinephrine

b) Increased production of vasopressin
c) Excess production of cortisol
d) Decreased secretion of cortisol
e) Decreased production of norepinephrine

Q30. A 73 year-old woman is shifted to ICU after she is found to be in septic shock. It is believed that
she had a urinary tract infection and bacteria seeded in bloodstream. Doctor is concerned she may
not have an adequate stress response in this situation. Which hormone is to be evaluated to check if
her body can respond to stress:

a) Oxytocin
b) Vasopressin
c) Cortisol
d) Corticotropin releasing hormone
e) ACTH

Q31. Which of the following is secreted in response to Angiotensin II :

a) Cortisol
b) Aldosterone
c) Thyroxine
d) Estrogen
e) FSH

Q32. A 23-year-old woman has been referred from an endocrinologist for weight gain, especially
around the waist. She also has purple striae over the abdomen and a rounded appearance to her
face. She is found to have Cushing’s disease. Which of the following can be seen in the patient:

a) Decreased absorption of glucose from the intestine

b) Decreased lipolysis
c) Increased protein synthesis
d) Increased gluconeogenesis
e) Decreased liver glycogen stores

Q33. Delta cells of pancreas produces which hormone :

a) Insulin
b) Glucagon
c) Somatostatin
d) Pancreatic amylase
e) Pancreatic polypeptide

Q34. How do steroid hormones produce their effects in cells?

a) By activating key enzymes in metabolic pathway
b) By binding to intracellular receptors and promoting transcription of specific genes
 c) By promoting the degradation of specific m-RNAs
d) By activating translation of certain m-RNA
e) By dephosphorylating the specific enzymes
Q35. Steroid hormones receptor binds to :
a) Hormone response elements in m-RNA
b) Hormone response elements in DNA
c) Hormone response elements in proteins
d) Ribosomes to stimulate translation
e) Hormone receptor elements in the ribosomes

Q36. Which steroid metabolite has the most carbon atoms and thus acts as an obligatory precursor
to the others?

a) Progesterone
b) Androgens
c) Estrogens
d) Aldosterone
e) Dehydroepiandrosterone

Q37. Which of the following statements best reflects the activity of sex steroids after they leave their
gland of origin?

a) Most steroid hormones are not bound to specific transport proteins as they circulate in the
bloodstream
b) Once inside the cell, a steroid can only produce responses in cells that have specific
intracellular receptors for that hormone
c) Steroid hormones dimerize in the cytoplasm before binding to its receptor
d) Steroids require transport proteins to enter cells
e) Each hormone have a unique sequence of events from entry into cells to protein synthesis

Q38. Which of the following statements regarding steroid excretion is true:

a) Steroid hormones are excreted as uric acid in urine

b) Steroids enter the nucleus and therefore cannot be excreted
c) Prior to elimination, most active steroids are conjugated as either sulphates or
glucuronides
d) Conjugated hormones completely loose their biological activity
e) Conjugated metabolites need protein carriers for elimination
Q39. After menopause there is an increase in secretion of :

a) FSH
b) LH
 c) Both FSH & LH
d) Estrogen
e) Progesterons

Q40. Pregnancy test is based on the presence of which hormone in the urine :

a) HCG
b) LH
c) FSH
d) Estrogen
e) Progesterone

Q41. A 28-year-old woman, mother of an 8-year old, notices that she has had no menstrual periods
for the past 6 months. she is not pregnant and takes no medications. Experiencing headaches for the
past 3 months. In the last week, she noted some milk like section from breasts. She is concerned
with her vision. An optometrist finds her lateral vision to be reduced. Which of the following
laboratory test findings is most likely to be present in this woman?

a) Increased serum cortisol

b) Lack of growth hormone suppression
c) Increased serum alkaline phosphatase
d) Hyperprolactinemia
e) Hyponatremia

Q42. Oxytocin is synthesized in the:

a) Anterior pituitary
b) Posterior pituitary
c) Adrenal medulla
d) Paraventricular nucleus of hypothalamus
e) Supraoptic nucleus of hypothalamus

Q43. Estradiol prevents osteoporosis in women of child bearing age by:

a) Antagonizing the effect of PTH

b) Increasing the Ca⁺⁺ absorption from intestine
c) Increasing the synthesis of calcitriol
d) Decreasing the release of calcium from intracellular stores
e) Antagonizing the effects of testosterone

Q44. Conversion of testosterone to estradiol requires the enzyme:

a) 5-α-reductase
b) Cytochrome P450
c) Aromatase
d) Desmolase
e) 17- hydroxylase
Q45. Increase in the glycogen content, mucin and fat deposition in the linning epithelium of uterine
endometrium are the effects of:

a) Estrogen
b) Progesterone
c) Β-hCG
d) Relaxin
e) Oxytocin

Q46. Androstenedione is the immediate precursor of:

a) Testosterone
b) Dihydroxytestosterone
c) Estrogen
d) Aldosterone
e) Corticosterone

Q47. Which steps in steroid synthesis is stimulated by ACTH:

a) Cholesterol → pregnenolone
b) Progesterone → 1-deoxycorticosterone
c) 17-hydroxypregnenolone → dehydro-epiandrosterone
d) Testosterone → estradiol
e) Testosterone → dihydrotestosterone

Q48. Bradycardia, sleepiness, slow reflexes, constipation and hypercholesterolemia are signs and
symptoms of:

a) Abnormal parathyroid function

b) Goitre
c) Myxedema
d) Graves disease
e) Congenital adrenal insufficiency

Q49. The growth hormone binds to its cell surface receptor and activates which of the following 2 nd
messenger molecule:

a) cGMP production
b) cAMP production
c) Tyrosine kinase activity
d) Calcium and Diacylglycerol
e) Calmodulin

Q50. Pro-opio-melanocorticotropin (POMC) is a precursor for which of the following peptides:

a) Adrenocorticotropic hormone (ACTH)

b) Thyroid Stimulating hormone (TSH)
c) Follicle stimulating hormone (FSH)
d) Luteinizing Hormone (LH)
e) Anti-Diuretic hormone (ADH)
Q51. Thyroid-stimulating hormone (TSH), luteinizing hormone (LH), and Follicular stimulating
hormone (FSH) are the hormones released from the anterior pituitary gland. Which of the following
is not a correct statement regarding these hormones :

a) They belong to the cholesterol family

b) Only LH and FSH has alpha and beta subunits
c) The alpha subunits are identical
d) The beta subunits are identical
e) They cross the cell membrane of their target cells

Q52. Which of the following conditions manifest as short stature:

a) Hypersecretion of Growth hormone-releasing hormone

b) Decreased secretion of islets of Langerhans
c) Hyposecretion of adrenal medulla
d) Hyposecretion of Growth hormone-releasing hormone
e) Hypersecretion of IGF from liver

Q53. The condition associated with the onset of hypersecretion of growth hormone in adults is
known as:

a) Gigantism
b) Dwarfism
c) Acromegaly
d) Goitre
e) Cretinism

Q54. A 50-years old man has "puffy" skin and is lethargic. His plasma TSH level is low and increased
markedly when he is given Thyrotropin-releasing hormone. What is the likely cause?

a) Hyperthyroidism due to a thyroid tumour

b) Hyperthyroidism due to an abnormality in the hypothalamus
c) Hypothyroidism due to an abnormality in the thyroid
d) Hypothyroidism due to an abnormality in the hypothalamus
e) Hypothyroidism due to iodine deficiency

Q55. The metabolic function of thyroid hormones include:

a) Decreased oxygen consumption

b) Increased lipogenesis
c) Increased Lipolysis
d) Protein Anabolism
e) Increased steroidogenesis

Q56. A 55 year old man with hyperthyroidism is treated with propylthiouracil. The drug reduces the
synthesis of thyroid hormones because it inhibits the oxidation of:

a) Triiodothyronine
b) Thyroxine
c) Diiodotyrosine
d) Iodide
e) Thyroglobulin
Q57. Which of the following is not the metabolic function of thyroid hormones:

a) Glycogenolysis
b) Gluconeogenesis
c) Glucose oxidation
d) Glycogenesis
e) Absorption of glucose from small intestine

Q58. Patients with Graves disease have high circulating levels of thyroid hormones. Graves disease is
characterized by the following :

a) Excess release of TSH from the anterior pituitary

b) Decreased activity of TSH receptor in thyroid glands
c) Presence of TSH receptor antibodies causing receptor activation
d) Increased deiodinase activity
e) Decreased secretion of T3 & T4

Q59. If insufficient PTH is produced the blood calcium level drops resulting in :

a) PTH dwarfism
b) Tetany
c) Osteoporosis
d) Blood clotting
e) Rickets

Q60. A hormone that is antagonist to PTH is secreted from :

a) Thyroid
b) Parathyroid
c) Adrenal cortex
d) Adrenal medulla
e) Hypothalamus

Q61. In a young boy of 15 years of age, plasma calcium level is diagnosed below optimum level,
which organ is suspected malfunctioning:

a) Thyroid
b) Parathyroid
c) Liver
d) Posterior lobe of pituitary
e) Anterior lobe of pituitary

Q62. Choose the mismatched pair regarding hormones and their deficiency diseases :

a) ADH ------- Diabetes Insipidus

b) Growth hormone ------ Acromegaly
c) Insulin ------ Diabetes Mellitus
d) Thyroxine ------ Grave’s disease
e) Aldosterone ------ Addisons disease

Q63. Which of the following factors is a potent inhibitor of glucagon secretion :

a) Hypoglycaemia
b) Hyperglycaemia
 c) Stress
d) Arginine
e) Lysine

Q64 Which of the following statements represent the action of insulin :

a) Increases blood glucose level by stimulating glucagon secretion

b) Decreases blood glucose level by synthesizing glycogen
c) Increases blood glucose level by promoting cellular uptake of glucose
d) Decreases blood glucose level by increasing urinary excretion of glucose
e) Increases blood glucose level by hydrolysis of glycogen

AA + Protein Met

Q65. Which one of the following statements concerning a one-week-old male infant with
undetected classic phenylketonuria is correct:

a) Tyrosine is a non-essential amino acid for the infant

b) High levels of phenylpyruvate appear in the urine
c) A diet devoid of phenylalanine should be initiated immediately
d) Therapy must begin within the first year of life
e) Skin hyperpigmentation is also one of the symptoms

Q66. Maple syrup disease is a disorder due to a deficiency of pathway that degrades:

a) Tyrosine
b) Tryptophan
c) Leucine
d) Methionine
e) arginine

Q67. Which of the following amino acids have an important role in the transport of amino groups
from peripheral tissues to the liver:

a) Serine
b) Methionine
c) Glutamine
d) Arginine
e) glycine

Q68. Cysteine is a nutritionally non-essential amino acid, and it is synthesized from:

a) Proline
b) Valine
c) Proline
d) Glycine
e) Methionine

Q69. Hydroxyproline and hydroxylysine are formed by hydroxylation of proline and lysine; the
reaction is catalyzed by prolyl and lysyl hydroxylase. Which of the following serve as coenzyme:

a) Biotin
b) Thiamine
 c) Ascorbate
d) Pyridoxal-P
a) Niacin

Q69. N-acetyl Glutamate is an activator of urea synthesis and is formed from condensation
glutamate and acetyl CoA. Which of the following enzyme catalyzes this reaction:

a) Arginosuccinate synthetase
b) Carbamoyl phosphate synthetase
c) N-Acetyl glutamate synthase
d) Glutaminase
e) Ornithine transcarbamoylase

Q70. A 55-year-old man diagnosed with cirrhosis of liver and ammonia in his body is not detoxifying
and can be damaging to brain. Which of the following amino acids can covalently link ammonia and
transport in a non toxic form:
a) Aspartate
b) Glutamate
c) Serine
d) Cysteine
e) Valine

Q71 In a newborn there were complaints of refusal to feeds and irritability, deficiency of
cystathionine-β-synthase is diagnosed. Which of the following compounds is expected to be
elevated:
a) Serine
b) Glutamate
c) Phenylacetate
d) Homocysteine
e) Vanillylmandelic acid

Q72. A -month-old infant is being evaluated for vomiting and an episode of convulsions. Laboratory
results show hyperammonemia and orotic aciduria. Which of the following enzyme defect is likely to
be there:
a) Glutathionase
b) Arginase
c) Argino-succinic acid synthase
d) Ornithine transcarbamoylase
e) Carbamoyl phosphate synthetase

Q73. Histamine a chemical mediator of allergies and anaphylaxis, is synthesized from amino acid
histidine by which of the following precursor:
a) Deamination
b) Decarboxylation
c) Transamination
d) Dehydrogenation
e) Carboxylation

Q74. The amino acid that undergoes oxidative deamination at the highest rate is:

a) Glutamine
 b) Glutamate
c) Aspartate
d) Alanine
e) Arginine

Q75. Dopamine is synthesized from which of the following amino acids:

a) Tyrosine
b) Tryptophan
c) Histidine
d) Methionine
e) Arginine

Q76. L-amino acids are absorbed from the intestine by:

a) Active transport
b) Passive diffusion
c) Pinocytosis
d) Facilitated diffusion
e) Phagocytosis
Q77. A patient diagnosed with Hartnup’s disease (due to the deficiency of transportes required for
the absorption of amino acid tryptophan), has been brought with skin rashes and suicidal
tendencies. Tryptophan is a precursor of many compounds the deficiencies of which can cause the
said symptoms. Which of the following compounds are synthesized by tryptophan:

a) Epinephrine
b) Norepinephrine
c) Melanin
d) Niacin
e) Phenylalanine
Q78. Which of the following is a common acceptor for all reactions involving transaminases:

a) α-keto-gluterate
b) Pyruvate
c) Oxaloacetate
d) Acetoacetate
e) Acetyl CoA

Q79. Tryptophan is best described by the following statement:

a) It produces thyroid hormones

b) It is a precursor for melanin
c) It is the precursor for pineal hormone, melatonin
d) It produces catecholamines
e) It is glucogenic only

Q80. A patient with a genetic defect in the enzyme Carbamoyl phosphate synthetase-1 would
present with:

a) Citrullinemia
 b) Arginine succinate aciduria
c) Hyperammonemia type-1
d) Hyperammonemia type-2
e) Hyperargininemia

Q81. Toxicity of ammonia is handled in brain by:

a) Converting it to urea
b) Increasing glycolysis
c) Binding it to glutamate
d) Producing more alanine
e) Synthesizing norepinephrine

Q82. Nitrogen balance is:

a) Negative in children
b) Negative during illness
c) Negative during high protein diet
d) Negative during convalescence
e) Unaffected in old age

Q83. The main sites for oxidative deamination are:

a) Liver and kidney

b) Skin, liver and kidney
c) Liver and spleen
d) Kidney and lungs
e) Kidney and RBC

Q84. Quantitatively the most important enzyme involved in the formation of NH₃ from amino acids in
humans is:

a) L-amino acid oxidase

b) Serine dehydratase
c) Glutamate dehydrogenase
d) Histidase
e) Desulfhydratase

Q85. All aminotransferases require the coenzyme:

a) Biotin
b) Pyridoxal phosphate
c) Thiamine pyrophosphate
d) NADP
e) FAD

Q86. Most of the ammonia released from L-amino acids reflects the coupled action of transaminase
and :
 a) L-glutamate dehydrogenase
b) L-amino acid oxidase
c) Histidase
d) Serine dehydratase
e) Urease

Q87. The 2 nitrogen atoms in urea are contributed by:

a) Ammonia and glutamate

b) Glutamine and glutamate
c) Ammonia and aspartate
d) Ammonia and alanine
e) Ammonia and glutamine

Q88. The first step in the catabolism of most amino acids is the transfer of their α-amino group to:

a) Pyruvate
b) Glutamate
c) Oxaloacetate
d) Aspartate
e) α-ketogluterate

Q89. Hyperammonemia type-1 is an inherited disorder due to the deficiency of which enzyme:

a) Carbamoyl phosphatase-I
b) Carbamoyl phosphatase-II
c) Ornithine transcarbamylase
d) Arginine-succinate synthetase
e) Arginine-succinase

90.cysteine is required for the synthesis of:

a) Heme
b) Cholesterol
c) Glutathione
d) Isoleucine
e) Methionine

Q91. Deficiency of branched chain α-keto acid dehydrogenase leads to:

a) Phenylketonuria
b) Albinism
c) Homocystinuria
d) Alkaptonuria
e) Maple syrup urine disease

Q92. Neurotransmitter 5-OH tryptamine:

a) Is synthesized from tyrosine

 b) Also known as serotonin
c) Can be blocked in the brain cells by the drug Reserpine
d) A mood depressant
e) Catabolized by monoamine oxidase (MAO) inhibitors

Q93. Malignancy of argentaffin cells lead to :

a) Hereditary tyrosinemia
b) Homocystinuria
c) Hartnup disease
d) Carcinoid syndrome
e) Alkaptonuria

Q94. Routine newborn screening identified a child with elevated levels of phenylpyruvate and
phenylacetate in the blood. Phenylalanine containing proteins were restricted from the diet. What
supplement can be added to avoid other amino acid deficiency:

a) Tyrosine
b) Glycine
c) Melanin
d) Phenylalanine
e) Alanine

Q95. Mousy odour of urine from the patients of phenylketonuria is due to the presence of which
metabolite in urine:

a) Phenyl acetyl glutamine

b) Phenylpyruvate
c) Alanine
d) Phenylalanine
e) Melanin

Q96. Decarboxylation of which amino acid produces γ-amino butyric acid (GABA):

a) Tyrosine
b) Tryptophan
c) Histidine
d) Glutamic acid
e) Aspartic acid

Q97. Another name for 5-hydroxytryptamine is:

a) Glutathione
b) Tyramine
c) β-alanine
d) Serotonin
e) Histamine

Q98. Lack of enzyme homogentisate oxidase results in rare inborn error of metabolism:
 a) Albinism
b) Tyrosinemia
c) Maple syrup urine disease
d) Phenylketonuria
e) Alkaptonuria

Q99 Which of the following amino acid produces a vasodilator on decarboxylation:

a) Glutamic acid
b) Histidine
c) Ornithine
d) Cysteine
e) Arginine

Q100. During degradation of amino acid leucine to acetyl CoA, it produces which compound that is a
metabolite in cholesterol synthesis:

a) β-methyl glutaryl-CoA
b) Isopententyl pyrophosphate
c) β-hydroxy-β-methyl glutaryl-CoA
d) Isoveralyl CoA
e) Faenesyl CoA

Q101 Serotonin is synthesized from :

a) Serene
b) Phenylalanine
c) Tyrosine
d) Tryptophan
e) Histidine

Q102. If one amino acid is fed excess, the absorption of another is:

a) Slightly accelerated
b) Moderately accelerated
c) Highly accelerated
d) Retarded
e) Not affected

Q103. Glutamate and Glutamine are nutritionally non-essential amino acids. The conversion of
alpha-ketoglutarate to glutamate and glutamine is catalysed by:

a) Glutamate synthetase and Glutamate dehydrogenase

b) Glutamate transaminases
c) Glutamate dehydrogenase and Glutamine synthetase
d) Glutamate dehydrogenase
e) Glutamate synthetase

Q104. Which coenzyme is required for the transamination reactions of most of the amino acids:
 a) FAD
b) FMN
c) Folic acid
d) Pyridoxal-P
e) Thiamine pyrophosphate

Q105 Which of the following is an important intermediate of urea cycle:

a) Serine
b) Glutamine
c) Proline
d) Leucine
e) Ornithine

Q106 Reaction of urea cycle in which urea is synthesized is catalysed by:

a) Carbamoyl phosphate synthetase I

b) Ornithine transcarbamoylase
c) Arginine-succinate synthetase
d) Arginase
e) Arginine-succinate lyase

Q107. Creatine phosphate :

a) Is a high energy phosphste compound

b) Is found in liver
c) Can not donate its phosphate
d) Is catalysed by monoamine oxidase enzyme
e) Finally degrades in urea

Q108. Excess nitrogen derived from the degradation of amino acids is excreted in urine in the form of
:

a) Ammonia
b) Creatinine
c) Aspartate
d) Urea
e) Uric acid

Q109. Which of the following statement about urea cycle is correct:

a) The 2 nitrogen atoms incorporated into urea enter the cycle as ammonia and glycine
b) Urea is produced directly by the hydrolysis of ornithine
c) Urinary urea is increased by a diet rich in proteins
d) ATP is required for the reaction where arginine-succinate is cleaved to form arginine
e) Urea cycle occurs exclusively in the mitochondria

Q110. Protein that have been chemically altered by addition of ubiquitin are most likely to be:
 a) Recreated from the cell
b) Degraded
c) Incorporated into the lysosomes
d) Transported to the nucleus
e) Transported out of the mitochondria

Q111. A newborn that appeared normal at birth developed lethargy, hypothermia and apnoea within
24 hours. These problems were traced to a deficiency of enzyme arginine-succinate synthetase. This
newborn would most likely to have:

a) High blood levels of urea

b) High blood levels of citrulline
c) High blood levels of arginine
d) Low blood levels of ammonia
e) Low blood levels of ornithine

Q112. The compound interlinking the TCA cycle and urea cycle is:

a) Malate
b) Citrate
c) Oxaloacetate
d) Fumarate
e) Succinate

Q113 In “Carcinoid syndrome” the intermittent diarrhoea and respiratory distress is due to the
increased formation of:

a) Tyramine
b) 5-OH tryptamine
c) Tryptophan
d) Histamine
e) GABA

Q114. Muscle protein loss can be estimated by determining in 24-hour sample for:

a) Ammonia
b) Urea
c) Uric acid
d) Ergothionine
e) 3-methyl histidine

Q115. Which enzyme is required for the catalysis of rate limiting step in urea cycle:

a) Carbamoyl phosphate synthetase I

b) Ornithine trans-carbamylase
c) Arginine-succinate synthetase
d) Arginine-succinate lyase
e) Arginase