BMSC 230 Final Exam Questions with
Correct Answers
What two amino acids are converted to oxaloacetate? - ANSWER-- asparagine
- aspartate
Enzyme for asparagine > aspartate - ANSWER-Asparaginase
Enzyme for aspartate > oxaloacetate - ANSWER-Aspartate aminotransferase
What amino acids are converted to a-ketoglutarate? - ANSWER-- glutamate
- glutamine
- arginine
- histidine
- proline
Enzyme for arginine > ornithine - ANSWER-Arginase
What are the byproducts of asparagine > aspartate? - ANSWER-- H2O
- NH4
What are the byproducts of aspartate > oxaloacetate? - ANSWER-- a-ketoglutarate
- glutamate
What are the byproducts of arginine > ornithine? - ANSWER-- H2O
- urea
What amino acids are converted to succinyl CoA? - ANSWER-- methionine
- isoleucine
- threonine
- valine
What are the intermediates of methionine, valine, & isoleucine to succinyl CoA? -
ANSWER-- propionyl CoA
- methylmalonyl CoA
What are the steps of degradation of methionine? - ANSWER-- methionine
- S-adenosylmethionine (SAM)
- S-adenosylhomocysteine
- homocysteine
- cystathionine
- a-ketobutyrate
- propionyl CoA
- succinyl CoA
, Enzyme for methionine > S-adenosylmethionine - ANSWER-Methionine adenosyl
transferase
What enzyme allows serine to be directly deaminated to pyruvate + NH4? -
ANSWER-Serine dehydratase
What enzyme allows threonine to be directle deaminated to a-ketobutyrate + NH4? -
ANSWER-Threonine dehydratase
Where are branched-chain amino acids mostly degraded? - ANSWER-- muscle
- adipose tissue
- kidney
- brain
What are branched-chain amino acids converted to first? By what? - ANSWER--
ketoacids
- branched-chain aminotransferase
What complex catalyzes oxidate decarboxylation of branched-chain amino acids?
What does this release? - ANSWER-- branched-chain a-keto acid dehydrogenase
complex
- releases the carboxyl group as CO2 & producing acyl-CoA deriviatives
What are the acyl CoA derivatives of leucine? - ANSWER-- a-ketoisocaproate
- acetyl CoA + acetoacetate
What are the acyl CoA derivatives of isoleucine? - ANSWER-- 2-keto-3-
methylvalerate
- acetyl CoA + propionyl CoA
What are the acyl CoA derivatives of valine? - ANSWER-- a-ketoisovalerate
- propionyl CoA
What is proprionyl CoA further converted to? - ANSWER-Succinyl CoA
What causes maple syrup urine disease? - ANSWER-A genetic defect in branched-
chain a-keto acid dehydrogenase resulting in the accumulation of ketoacids
What are the steps in the degradation of leucine to acetyl CoA + acetoacetate? -
ANSWER-- leucine
- a-ketoisocaproate
- isovaleryl CoA
- b-methylglutaconyl CoA
- 3-hydroxy-3-methylglutaryl CoA
- acetyl CoA + acetoacetate
Enzyme for phenylalanine > tyrosine - ANSWER-Phenylalanine hydroxylase
Correct Answers
What two amino acids are converted to oxaloacetate? - ANSWER-- asparagine
- aspartate
Enzyme for asparagine > aspartate - ANSWER-Asparaginase
Enzyme for aspartate > oxaloacetate - ANSWER-Aspartate aminotransferase
What amino acids are converted to a-ketoglutarate? - ANSWER-- glutamate
- glutamine
- arginine
- histidine
- proline
Enzyme for arginine > ornithine - ANSWER-Arginase
What are the byproducts of asparagine > aspartate? - ANSWER-- H2O
- NH4
What are the byproducts of aspartate > oxaloacetate? - ANSWER-- a-ketoglutarate
- glutamate
What are the byproducts of arginine > ornithine? - ANSWER-- H2O
- urea
What amino acids are converted to succinyl CoA? - ANSWER-- methionine
- isoleucine
- threonine
- valine
What are the intermediates of methionine, valine, & isoleucine to succinyl CoA? -
ANSWER-- propionyl CoA
- methylmalonyl CoA
What are the steps of degradation of methionine? - ANSWER-- methionine
- S-adenosylmethionine (SAM)
- S-adenosylhomocysteine
- homocysteine
- cystathionine
- a-ketobutyrate
- propionyl CoA
- succinyl CoA
, Enzyme for methionine > S-adenosylmethionine - ANSWER-Methionine adenosyl
transferase
What enzyme allows serine to be directly deaminated to pyruvate + NH4? -
ANSWER-Serine dehydratase
What enzyme allows threonine to be directle deaminated to a-ketobutyrate + NH4? -
ANSWER-Threonine dehydratase
Where are branched-chain amino acids mostly degraded? - ANSWER-- muscle
- adipose tissue
- kidney
- brain
What are branched-chain amino acids converted to first? By what? - ANSWER--
ketoacids
- branched-chain aminotransferase
What complex catalyzes oxidate decarboxylation of branched-chain amino acids?
What does this release? - ANSWER-- branched-chain a-keto acid dehydrogenase
complex
- releases the carboxyl group as CO2 & producing acyl-CoA deriviatives
What are the acyl CoA derivatives of leucine? - ANSWER-- a-ketoisocaproate
- acetyl CoA + acetoacetate
What are the acyl CoA derivatives of isoleucine? - ANSWER-- 2-keto-3-
methylvalerate
- acetyl CoA + propionyl CoA
What are the acyl CoA derivatives of valine? - ANSWER-- a-ketoisovalerate
- propionyl CoA
What is proprionyl CoA further converted to? - ANSWER-Succinyl CoA
What causes maple syrup urine disease? - ANSWER-A genetic defect in branched-
chain a-keto acid dehydrogenase resulting in the accumulation of ketoacids
What are the steps in the degradation of leucine to acetyl CoA + acetoacetate? -
ANSWER-- leucine
- a-ketoisocaproate
- isovaleryl CoA
- b-methylglutaconyl CoA
- 3-hydroxy-3-methylglutaryl CoA
- acetyl CoA + acetoacetate
Enzyme for phenylalanine > tyrosine - ANSWER-Phenylalanine hydroxylase
