Description : The four nitrogen atoms of purines are derived from (A) Urea and NH3 (B) NH3, Glycine and Glutamate (C) NH3, Asparate and Glutamate (D) Aspartate, Glutamine and Glycine
Last Answer : Answer : D
Description : The two nitrogen of the pyrimidine ring are contributed by (A) Ammonia and glycine (B) Asparate and carbamoyl phosphate (C) Glutamine and ammonia (D) Aspartate and ammonia
Last Answer : Answer : B
Description : A key substance in the committed step of pyrimidines biosynthesis is (A) Ribose-5-phosphate (B) Carbamoyl phosphate (C) ATP (D) Glutamine
Description : Folic acid or folate consists of the (A) Base pteridine, p-amino benzoic acid and asparate (B) Base purine, p-amino benzoic acid and glutamate (C) Base pteridine, p-amino benzoic acid and glutamate (D) Base purine, p-hydroxy benzoic acid and glutamate
Last Answer : Answer : C
Description : Which of the following contributes nitrogen atoms to both purine and pyrimidine rings? (A) Aspartate (B) Carbamoyl phosphate (C) CO2 (D) Glutamine
Last Answer : Answer : A
Description : Nitrogen at position 3 of pyrimidine nucleus comes from (A) Glutamine (B) Glutamate (C) Glycine (D) Aspartate
Description : Nitrogen at position 1 of pyrimidine nucleus comes from (A) Glutamine (B) Glutamate (C) Glycine (D) Aspartate
Description : The nitrogen atoms of pyrimidine nucleus are provided by (A) Glutamate (B) Glutamate and aspartate (C) Glutamine (D) Glutamine and aspartate
Description : The nitrogen atoms for de novo synthesis of purine nucleotides are provided by (A) Aspartate and glutamate (B) Aspartate and glycine (C) Aspartate, glutamine and glycine (D) Aspartate, glutamate and glycine
Description : 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
Description : Alanine can be synthesized from (A) Glutamate and α-ketoglutarate (B) Pyruvate and glutamate (C) Pyruvate and α-ketoglutarate (D) Asparate and α-ketoglutarate
Description : Electrostatic bonds can be formed between the side chains of (A) Alanine and leucine (B) Leucine and valine (C) Asparate and glutamate (D) Lysine and aspartate
Description : Two nitrogen atoms of Urea in the urea cycle come from (A) NH3 (B) One from NH3 and one from aspartate (C) One from NH3 and one from glutamate (D) One from NH3 and one from alanine
Description : Free ammonia is released during (A) Oxidative deamination of glutamate (B) Catabolism of purines (C) Catabolism of pyrimidines (D) All of these
Description : Cytosolic carbamoyl phosphate synthetase is activated by (A) Glutamine (B) PRPP (C) ATP (D) Aspartate
Description : Pyrimidine biosynthesis begins with the formation from glutamine, ATP and CO2, of (A) Carbamoyl aspartate (B) Orotate (C) Carbamoyl phosphate (D) Dihydroorotate
Description : Hyperammonaemia type I results from congenital absence of (A) Glutamate dehydrogenase (B) Carbamoyl phosphate synthetase (C) Ornithine transcarbamoylase (D) None of these
Description : Carbamoyl phosphate synthetase structure is marked by change in the presence of (A) N-Acetyl glutamate (B) N-Acetyl Aspartate (C) Neuraminic acid (D) Oxalate
Description : The metabolite which sustains urea cycle is (A) Ornithine (B) Citrulline (C) Carbamoyl phosphate (D) n-acetyl glutamate
Description : Transfer of the carbamoyl moiety of carbamoyl phosphate to ornithine is catalysed by a liver mitochondrial enzyme: (A) Carbamoyl phosphate synthetase (B) Ornithine transcarbamoylase (C) N-acetyl glutamate synthetase (D) N-acetyl glutamate hydrolase
Description : L-glutamic acid is subjected to oxidative deaminition by (A) L-amino acid dehydrogenase (B) L-glutamate dehydrogenase (C) Glutaminase (D) Glutamine synthetase
Description : CTP synthetase forms CTP from (A) CDP and inorganic phosphate (B) CDP and ATP (C) UTP and glutamine (D) UTP and glutamate
Description : For synthesis of CTP and UTP, the amino group comes from (A) Amide group of Asparagine (B) Amide group of glutamine (C) α-Amino group of glutamine (D) α-Amino group of glutamate
Description : The carbon atoms of pyrimidine nucleus are provided by (A) Glycine and aspartate (B) CO2 and aspartate (C) CO2 and glutamate (D) CO2 and glutamine
Description : NH+ 4 aminates glutamate to form glutamine requiring ATP and (A) K+ (B) Na+ (C) Ca++ (D) Mg++
Description : In brain, the major metabolism for removal of ammonia is the formation of (A) Glutamate (B) Aspartate (C) Asparagine (D) Glutamine
Description : The amino acid that undergoes oxidative deamination at significant rate is (A) Alanine (B) Aspartate (C) Glutamate (D) Glutamine
Description : All of the following are required for synthesis of glutamine except (A) Glutamate (B) Ammonia (C) Pyridoxal phosphate (D) ATP
Description : Synthesis of GMP and IMP requires the following: (A) NH3 NAD+, ATP (B) Glutamine, NAD+, ATP (C) NH3, GTP, NADP+ (D) Glutamine, GTP, NADP+
Description : The major source of NH3 produced by the kidney is (A) Leucine (B) Glycine (C) Alanine (D) Glutamine
Description : NH3 is removed from brain mainly by (A) Creatinine formation (B) Uric acid production (C) Urea formation (D) Glutamine formation
Description : NH3 is detoxified in brain chiefly as (A) Urea (B) Uric acid (C) Creatinine (D) Glutamine
Description : During de novo synthesis of pyrimidine nucleotides, the first ring compound to be formed is (A) Carbamoyl aspartic acid (B) Dihydro-orotic acid (C) Orotic acid (D) Orotidine monophosphate
Description : In purine nucleus nitrogen atom at 1 position is derived from (A) Aspartate (B) Glutamate (C) Glycine (D) Alanine
Description : The major end product of protein nitrogen metabolism in man is (A) Glycine (B) Uric acid (C) Urea (D) NH3
Description : In humans, the principal metabolic product of pyrimidines is (A) Uric acid (B) Allantoin (C) Hypoxanthine (D) β-alanine
Description : The probable metabolic defect in gents is (A) A defect in excretion of uric acid by kidney (B) An overproduction of pyrimidines (C) An overproduction of uric acid (D) Rise in calcium leading to deposition of calcium urate
Description : Uric acid is the catabolic end product of (A) Porphyrine (B) Purines (C) Pyrimidines (D) Pyridoxine
Description : Nucleic acids can be detected by means of their absorption maxima near 260 nm. Their absorption in this range is due to (A) Proteins (B) Purines and pyrimidines (C) Ribose (D) Deoxyribose
Description : Which of the following statements about nucleic acid is most correct? (A) Both pentose nucleic acid and deoxypentose nucleic acid contain the same pyrimidines (B) Both pentose nucleic acid and deoxypentose ... (C) RNA contains cytosine and thymine (D) DNA and RNA are hydrolysed by weak alkali
Description : Orotic aciduria can be controlled by (A) Oral administration of orotic acid (B) Decreasing the dietary intake of orotic acid (C) Decreasing the dietary intake of pyrimidines (D) Oral administration of uridine
Description : The major catabolic product of pyrimidines in human is (A) β-Alanine (B) Urea (C) Uric acid (D) Guanine
Description : Methylated purines and pyrimidines are characteristically present in (A) mRNA (B) hnRNA (C) tRNA (D) rRNA
Description : Identify the correct molecule which controls the biosynthesis of proteins in living organisms. (A) DNA (B) RNA (C) Purines (D) Pyrimidines
Description : Glycine is not required for the formation of (A) Taurocholic acid (B) Creatine (C) Purines (D) Pyrimidines
Description : The first stable product of fixation of atmospheric nitrogen in leguminous plants is (a) NO3 − (b) glutamate (c) NO2 − (d) ammonia
Last Answer : (c) NO2
Description : Cytosolic carbamoyl phosphate synthetase is inhibited by (A) UTP (B) CTP (C) PRPP (D) TMP
Description : De novo synthesis of pyrimidine nucleotides is regulated by (A) Carbamoyl phosphate synthetase (B) Aspartate transcarbamoylase (C) Both (A) and (B) (D) None of these
Description : All the enzymes required for de novo synthesis of pyrimidine nucleotides are cytosolic except (A) Carbamoyl phosphate synthetase (B) Aspartate transcarbamoylase (C) Dihydro-orotase (D) Dihydro-orotate dehydrogenase
Description : An enzyme common to de novo synthesis of pyrimidine nucleotides and urea is (A) Urease (B) Carbamoyl phosphate synthetase (C) Aspartate transcarbamoylase (D) Argininosuccinase