BICH 411 Final Exam Review Questions and Answers
1. an infant won't eat, has persistent vomiting, is lethargic and is failing to thrive. these are the
classic symptoms of hyperammonemia. a blood sample confirms this hypothesis and also reveals
that the circulating plasma concen- tration of urea extremely low. a biopsy of the liver showed
abnormally high levels or arginosuccinate with no detectable arginine. the infant most likely has
a defect in : arginosuccinate lyase
2. what is the carbon source is urea?: HCO3-
3. which of the following cannot travel through the liver mitochondrial mem- brane?: NH4+
4. what is the function of N-acetylglutamate?: N-acetylglutamate activates car- bamoyl phosphate
synthetase I (CPS I)
5. early in its life, a tadpole lives in an aqueous environment and excretes much of its excess
nitrogen as ammonia. once it matures into an adult, the frog spends more time on dry ground and
becomes ureotelic. which of the following enzyme activities would be the most likely to increase
drastically in the adult frog?: CPS I
6. aspartate aminotransferase: requires PLP
7. the reaction, glutamate + NAD(P)+ + H2O -> NH4+ + alpha-ketoglutarate + NAD(P)H + H+,
is catalyzed by : glutamate dehydrogenase (GDH)
8. which enzymes catalyze ATP-dependent reactions in the urea cycle?: -
arginosuccinate synthetase and CPS I
9. glutamine synthase activity is found highest in which compartment?: mus- cle tissue
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, BICH 411 Final Exam Review Questions and Answers
10.applies to ornithine transcarbamoylase: most common enzyme deficiency leading to urea
cycle disorder
11.in the alanine cycle, : pyruvate is the "energy" product of the cycle
12.what is true of the reaction catalyzed by glutamate dehydrogenase?: - NH4+ is produced
- the enzymes can use either NAD+ or NADP+ as a cofactor
- the enzyme is glutamate-specific
- beta-3-ketoglutarate is produced from an amino acid
13.what is the intermediate for arginosuccinate synthetase?: adenylated inter- mediate
14.what is used to excrete excess nitrogen by living organisms?: - ammonia
- urea
- uric acid
15.carbamate is the intermediate for what enzyme?: carbamoyl phosphate syn- thetase I
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1. an infant won't eat, has persistent vomiting, is lethargic and is failing to thrive. these are the
classic symptoms of hyperammonemia. a blood sample confirms this hypothesis and also reveals
that the circulating plasma concen- tration of urea extremely low. a biopsy of the liver showed
abnormally high levels or arginosuccinate with no detectable arginine. the infant most likely has
a defect in : arginosuccinate lyase
2. what is the carbon source is urea?: HCO3-
3. which of the following cannot travel through the liver mitochondrial mem- brane?: NH4+
4. what is the function of N-acetylglutamate?: N-acetylglutamate activates car- bamoyl phosphate
synthetase I (CPS I)
5. early in its life, a tadpole lives in an aqueous environment and excretes much of its excess
nitrogen as ammonia. once it matures into an adult, the frog spends more time on dry ground and
becomes ureotelic. which of the following enzyme activities would be the most likely to increase
drastically in the adult frog?: CPS I
6. aspartate aminotransferase: requires PLP
7. the reaction, glutamate + NAD(P)+ + H2O -> NH4+ + alpha-ketoglutarate + NAD(P)H + H+,
is catalyzed by : glutamate dehydrogenase (GDH)
8. which enzymes catalyze ATP-dependent reactions in the urea cycle?: -
arginosuccinate synthetase and CPS I
9. glutamine synthase activity is found highest in which compartment?: mus- cle tissue
1/3
, BICH 411 Final Exam Review Questions and Answers
10.applies to ornithine transcarbamoylase: most common enzyme deficiency leading to urea
cycle disorder
11.in the alanine cycle, : pyruvate is the "energy" product of the cycle
12.what is true of the reaction catalyzed by glutamate dehydrogenase?: - NH4+ is produced
- the enzymes can use either NAD+ or NADP+ as a cofactor
- the enzyme is glutamate-specific
- beta-3-ketoglutarate is produced from an amino acid
13.what is the intermediate for arginosuccinate synthetase?: adenylated inter- mediate
14.what is used to excrete excess nitrogen by living organisms?: - ammonia
- urea
- uric acid
15.carbamate is the intermediate for what enzyme?: carbamoyl phosphate syn- thetase I
2/3
