TEST BANK; Gerontology HESI (540 Questions with all Correct
Answers| Verified (Latest) Graded A+
Which of the following reactions of the urea cycle takes place in the
mitochondria? - Answer The synthesis of carbamoyl phosphate
Several amino acids are intermediates of the urea cycle, having side ammonia
groups that join with free carbon dioxide (CO2) and ammonia to produce net
excretion of ammonia as urea. Which of the following amino acids has a nitrogen
in its side chain and is an intermediate of the urea cycle? - Answer Arginine
Homocystinuria can be caused by several different enzyme or vitamin
deficiencies. An elevation of homocysteine and a decrease in cysteine would
most likely present due to which of the following deficiencies? - Answer Loss of
function of cystathionine-β synthase
In an individual with a deficiency in the branched chain ketoacid dehydrogenase
complex, metabolism of which of the following amino acids would not likely be
impaired? - Answer Tyrosine
S-adenosylmethionine (SAM) is synthesized from ATP and methionine. A
deficiency in which of the following enzymes would impair the production of
SAM? - Answer Methionine adenosyltransferase (MAT)
The conversion of ribose bases into deoxy-bases will be occurring under which
of the following conditions? - Answer When cells are proliferating
A patient recently diagnosed with colon cancer is being treated with 5-
fluorouracil. Which of the following enzymes will this drug directly inhibit? -
Answer Thymidylate synthase
,A comatose infant is brought to the ER. In the course of the examination, plasma
ammonia was found to be elevated 20-fold over normal values. Urine orotic acid
and uracil were both greater than normal. A defect of which of the following
enzymes is the most likely diagnosis? - Answer Ornithine transcarbamoylase
Your patient presents with a deficiency of the enzyme that catalyzes synthesis of
N-acetylglutamate (NAGs). Which of the following would be a consequence of this
deficiency in the patient? - Answer Increased amino acids in the blood
The cellular uptake of LDL increases intracellular cholesterol levels. This has
which of the following impacts on de novo cholesterol synthesis? - Answer
Increases degradation of HMG-CoA reductase
Dietary cholesterol is primarily transported in the body by which of the following
lipoproteins? - Answer Chylomicron
Secondary bile salts are generated by bacterial modification of primary bile salts
in the intestinal lumen. These modifications have which of the following impacts
on bile salt solubility? - Answer Decrease solubility
A 47-year-old male is prescribed a statin (HMG-CoA reductase inhibitor) to
manage his elevated LDL cholesterol. What is the initial mechanism of action for
obtaining the desired effect in this man? - Answer Decreasing hepatic cholesterol
biosynthesis
A deficiency in the LDL receptor will result in an initial decrease in which of the
following? - Answer Intracellular cholesterol
,A 45-year-old man has a mild heart attack and a history of vascular disease. He is
placed on a Mediterranean diet and statin drug therapy. Which of the following
will be the most likely result of this drug therapy? - Answer Low blood LDLs
A 45-year-old man is found to have an elevated serum triglycerides of >
730mg/dL. He tells you he forgot to fast before his visit and he ate a full breakfast
of bacon and eggs before the labs were drawn. Which of the following
lipoproteins would be the largest contributors to a measurement of plasma
triglycerides in this situation? - Answer Chylomicrons and VLDLs
In the reaction catalyzed by cholesterol ester transfer protein (CETP), the VLDL
particle receives which of the following compounds from HDL particles? -
Answer Cholesterol-ester
In reverse cholesterol transport HDL interacts with the ABCA1 transporter to
move cholesterol from the cell to the HDL. This also requires the activity of which
of the following enzyme? - Answer Lecithin cholesterol acyltransferase (LCAT)
HDL particles interact with VLDL particles to exchange cholesterol ester for
triacylglyerols. Which of the following enzymes is responsible for this process? -
Answer Cholesterol ester transfer protein (CETP)
Which of the following is a major source of extracellular cholesterol for human
tissues? - Answer LDLs
An individual is suspected of having a deficiency in branched chain keto acid
dehydrogenase. Supplementation of which of the following vitamins or cofactors
may help resolve this issue? - Answer Thiamine
A 55-year old man presents to his primary care physician with bouts of dizziness
and confusion. He is diagnosed with hyperhomocysteinemia due to a deficiency
, of cystathionine-ß synthase. In this individual which of the following amino acids
could potentially become essential? - Answer Cysteine
Phenylketonuria can be caused by an enzymatic deficiency or it can present due
to a deficiency in which of the following required metabolic cofactors? - Answer
Tetrahydrobiopterin (BH4)
A 17-year old female presents to her primary care and is diagnosed with a Vitamin
B12 (cobalamin) deficiency. In this individual, which of the following reactions
would be compromised? - Answer Conversion of methyl malonyl-Co A to succinyl-
CoA
A 15-year-old female presents to her pediatrician with concerns over her inability
to sleep, increased feelings of depression and generalized fatigue. A full
laboratory work-up is ordered and based on these findings she is diagnosed with
a melatonin deficiency. Based on this information, metabolism of which of the
following amino acids is likely impaired? - Answer Tryptophan
A 52-year- old male sought medical help complaining about progressive
appearance of hyperchromic (hyper pigmented) papules on the edge of the
second finger of both hands. He also complained about darkening of urine.
Incisional biopsy of one of the spots on his hands and urine sample tested
positive for or homogentisic acid. Based on these findings a diagnosis of
alkaptonuria is made. This diagnosis is consistent with a deficiency in which of
the following enzymes? - Answer Homogentisate oxidase
Methotrexate is a potent anticancer agent that starves dividing cells of
deoxyribonucleotides through direct inhibition of which of the following
processes? - Answer Metabolism of folic acid
Answers| Verified (Latest) Graded A+
Which of the following reactions of the urea cycle takes place in the
mitochondria? - Answer The synthesis of carbamoyl phosphate
Several amino acids are intermediates of the urea cycle, having side ammonia
groups that join with free carbon dioxide (CO2) and ammonia to produce net
excretion of ammonia as urea. Which of the following amino acids has a nitrogen
in its side chain and is an intermediate of the urea cycle? - Answer Arginine
Homocystinuria can be caused by several different enzyme or vitamin
deficiencies. An elevation of homocysteine and a decrease in cysteine would
most likely present due to which of the following deficiencies? - Answer Loss of
function of cystathionine-β synthase
In an individual with a deficiency in the branched chain ketoacid dehydrogenase
complex, metabolism of which of the following amino acids would not likely be
impaired? - Answer Tyrosine
S-adenosylmethionine (SAM) is synthesized from ATP and methionine. A
deficiency in which of the following enzymes would impair the production of
SAM? - Answer Methionine adenosyltransferase (MAT)
The conversion of ribose bases into deoxy-bases will be occurring under which
of the following conditions? - Answer When cells are proliferating
A patient recently diagnosed with colon cancer is being treated with 5-
fluorouracil. Which of the following enzymes will this drug directly inhibit? -
Answer Thymidylate synthase
,A comatose infant is brought to the ER. In the course of the examination, plasma
ammonia was found to be elevated 20-fold over normal values. Urine orotic acid
and uracil were both greater than normal. A defect of which of the following
enzymes is the most likely diagnosis? - Answer Ornithine transcarbamoylase
Your patient presents with a deficiency of the enzyme that catalyzes synthesis of
N-acetylglutamate (NAGs). Which of the following would be a consequence of this
deficiency in the patient? - Answer Increased amino acids in the blood
The cellular uptake of LDL increases intracellular cholesterol levels. This has
which of the following impacts on de novo cholesterol synthesis? - Answer
Increases degradation of HMG-CoA reductase
Dietary cholesterol is primarily transported in the body by which of the following
lipoproteins? - Answer Chylomicron
Secondary bile salts are generated by bacterial modification of primary bile salts
in the intestinal lumen. These modifications have which of the following impacts
on bile salt solubility? - Answer Decrease solubility
A 47-year-old male is prescribed a statin (HMG-CoA reductase inhibitor) to
manage his elevated LDL cholesterol. What is the initial mechanism of action for
obtaining the desired effect in this man? - Answer Decreasing hepatic cholesterol
biosynthesis
A deficiency in the LDL receptor will result in an initial decrease in which of the
following? - Answer Intracellular cholesterol
,A 45-year-old man has a mild heart attack and a history of vascular disease. He is
placed on a Mediterranean diet and statin drug therapy. Which of the following
will be the most likely result of this drug therapy? - Answer Low blood LDLs
A 45-year-old man is found to have an elevated serum triglycerides of >
730mg/dL. He tells you he forgot to fast before his visit and he ate a full breakfast
of bacon and eggs before the labs were drawn. Which of the following
lipoproteins would be the largest contributors to a measurement of plasma
triglycerides in this situation? - Answer Chylomicrons and VLDLs
In the reaction catalyzed by cholesterol ester transfer protein (CETP), the VLDL
particle receives which of the following compounds from HDL particles? -
Answer Cholesterol-ester
In reverse cholesterol transport HDL interacts with the ABCA1 transporter to
move cholesterol from the cell to the HDL. This also requires the activity of which
of the following enzyme? - Answer Lecithin cholesterol acyltransferase (LCAT)
HDL particles interact with VLDL particles to exchange cholesterol ester for
triacylglyerols. Which of the following enzymes is responsible for this process? -
Answer Cholesterol ester transfer protein (CETP)
Which of the following is a major source of extracellular cholesterol for human
tissues? - Answer LDLs
An individual is suspected of having a deficiency in branched chain keto acid
dehydrogenase. Supplementation of which of the following vitamins or cofactors
may help resolve this issue? - Answer Thiamine
A 55-year old man presents to his primary care physician with bouts of dizziness
and confusion. He is diagnosed with hyperhomocysteinemia due to a deficiency
, of cystathionine-ß synthase. In this individual which of the following amino acids
could potentially become essential? - Answer Cysteine
Phenylketonuria can be caused by an enzymatic deficiency or it can present due
to a deficiency in which of the following required metabolic cofactors? - Answer
Tetrahydrobiopterin (BH4)
A 17-year old female presents to her primary care and is diagnosed with a Vitamin
B12 (cobalamin) deficiency. In this individual, which of the following reactions
would be compromised? - Answer Conversion of methyl malonyl-Co A to succinyl-
CoA
A 15-year-old female presents to her pediatrician with concerns over her inability
to sleep, increased feelings of depression and generalized fatigue. A full
laboratory work-up is ordered and based on these findings she is diagnosed with
a melatonin deficiency. Based on this information, metabolism of which of the
following amino acids is likely impaired? - Answer Tryptophan
A 52-year- old male sought medical help complaining about progressive
appearance of hyperchromic (hyper pigmented) papules on the edge of the
second finger of both hands. He also complained about darkening of urine.
Incisional biopsy of one of the spots on his hands and urine sample tested
positive for or homogentisic acid. Based on these findings a diagnosis of
alkaptonuria is made. This diagnosis is consistent with a deficiency in which of
the following enzymes? - Answer Homogentisate oxidase
Methotrexate is a potent anticancer agent that starves dividing cells of
deoxyribonucleotides through direct inhibition of which of the following
processes? - Answer Metabolism of folic acid
