Question

a)The urea cycle:The reciprocal substrate relationship (ATP vs GTP) in purine nucleotide synthesis ensures a balanced pool of adenine nucleotide and guanidine nucleotide be available for the synthesis of nucleic acid. True/False?

b) The urea cycle:converts urea to ammonia and carbon dioxide.True/False?

c) The urea cycle: acts as an energy-supplying mechanism by oxidizing waste materials.True/False?

d) The urea cycle:converts ammonia into urea. True/False?

e) The urea cycle:converts urea into uric acid. True/False?

f) The urea cycle:supplies the bodily requirement for arginine in adults. True/False?

g) For mammals, some amino acids are essential in the diet, whereas others may be formed from dietary components. Humans are capable of converting: oxaloacetate to aspartic acid. True/False?

Answer 1

• Option A is true as the reciprocal relationship of the substrate such as ATP and GTP that is ATP act as a substrate to synthesis GMP and GTP as the substrate to synthesis AMP acts as the control for the synthesis of nucleic at two that in the inosinate and conversion of PRPP to phosphoribosylamine.
• In the urea cycle, the amino acid from the liver mitochondrial matrix combines with CO2 to form carbamoyl phosphate in the mitochondrial matrix. So option B is false that is ammonia and CO2 combine to form urea, not vice verse.
• Option C is true as the fumarate generated during the formation of argininosuccinate forms malate in the citric acid cycle with the generation of a molecule of NADH that is equivalent to 2.5 ATP. Thus act as the energy source by oxidizing waste products.
• Option D is true as the ammonia from the liver mitochondrial matrix from various sources such as from bacteria oxidation, and intestine combine with CO2 to form the carbamoyl phosphate with the carbamoyl phosphate synthetase I and get activated with utilization ATP thus enters the mitochondrial cytosol to begin urea cycle.
• Option E is false as in the urea cycle urea is produced the urea. The uric acid occurs in the de novo synthesis of the purine that in the biosynthesis of the purines.
• The N-acetyl glutamate is required for the production of carbamoyl phosphate from the ammonia and CO2 which is synthesized from the cetyl CoA and glutamate. And the arginine is the activator of N-acetyl glutamate synthetase thus act as the activator of the urea cycle. And in the urea cycle arginine undergoes cleavage to release urea so option F is false as n the urea cycle arginine is utilized not supplied to the body. Thus serve as the control of arginine production.
• Option G is true as for the mammals some amino acids are essential such as linoleic acid, linolenic acid, and arachidonic acid which they obtain in from the diet while some other amino acids are produced from these dietary components that is essential amino acids. And the human is capable of converting oxaloacetate into arginine by the first oxaloacetate undergoes citric acid cycle to form aspartate which then enter aspartate-argininosuccinate shunt to form argininosuccinate which in urea cycle with the help of arginase form arginine so the statement is true.