Question 1

The LARGEST energy store in a well-nourished human is:

Accepted Answer

A)  ATP in all tissues. 
B)  blood glucose. 
C)  liver glycogen. 
D)  muscle glycogen. 
E)  triacylglycerols in adipose tissue. 
A)  ATP in all tissues. 
B)  blood glucose. 
C)  liver glycogen. 
D)  muscle glycogen. 
E)  triacylglycerols in adipose tissue.

Question 2

Each enzyme listed below catalyzes a reaction in the skeletal muscles of an Olympic sprinter. However, the role of which one would be considered LEAST significant during the running of a 100m sprint?

Accepted Answer

A)  adenylate kinase 
B)  creatine kinase 
C)  pyruvate dehydrogenase 
D)  lactate dehydrogenase 
E)  glycogen phosphorylase 
A)  adenylate kinase 
B)  creatine kinase 
C)  pyruvate dehydrogenase 
D)  lactate dehydrogenase 
E)  glycogen phosphorylase

Question 3

Describe five possible fates of amino acids arriving in the liver after intestinal uptake.

Accepted Answer

1. Conversion to glucose: Some amino aci

Question 4

Which factor is NOT involved in triggering insulin from $\beta$-cells release in response to glucose?

Accepted Answer

A)  reduced efflux through ATP-gated K+-channels 
B)  increased concentrations of ATP 
C)  cAMP-dependent phosphorylation of lipase 
D)  phosphorylation of glucose to glucose-6-phosphate 
E)  increased Ca2+ levels 
A)  reduced efflux through ATP-gated K+-channels 
B)  increased concentrations of ATP 
C)  cAMP-dependent phosphorylation of lipase 
D)  phosphorylation of glucose to glucose-6-phosphate 
E)  increased Ca2+ levels

Question 5

What explains the relative resistance to hypoglycemic coma in people who are starving compared with a normal person?

Accepted Answer

The relative resistance to hypoglycemic

Question 6

An example of a steroid hormone is:

Accepted Answer

A)  epinephrine. 
B)  retinoic acid. 
C)  testosterone. 
D)  thromboxane. 
E)  thyroxine. 
A)  epinephrine. 
B)  retinoic acid. 
C)  testosterone. 
D)  thromboxane. 
E)  thyroxine.

Question 7

Which statement describes one of the roles of mTORC1?

Accepted Answer

A)  mTORC1 activates AMP-activated protein kinase (AMPK), resulting in energy production for cell growth. 
B)  mTORC1 activates translation of proteins involved in lipid synthesis and mitochondrial metabolism. 
C)  mTORC1 acts through AMPK to increase sensitivity of hepatocytes and myocytes to insulin. 
D)  mCTOR1 reduces the uptake of glucose by hepatocytes, ensuring the brain has an adequate glucose supply. 
E)  All of the answers are correct. 
A)  mTORC1 activates AMP-activated protein kinase (AMPK), resulting in energy production for cell growth. 
B)  mTORC1 activates translation of proteins involved in lipid synthesis and mitochondrial metabolism. 
C)  mTORC1 acts through AMPK to increase sensitivity of hepatocytes and myocytes to insulin. 
D)  mCTOR1 reduces the uptake of glucose by hepatocytes, ensuring the brain has an adequate glucose supply. 
E)  All of the answers are correct.

Question 8

The hormone leptin _____ appetite; insulin _____ appetite.

Accepted Answer

A)  increases; increases 
B)  increases; decreases 
C)  decreases; increases 
D)  decreases; decreases 
E)  has no effect on; has no effect on 
A)  increases; increases 
B)  increases; decreases 
C)  decreases; increases 
D)  decreases; decreases 
E)  has no effect on; has no effect on

Question 9

The normal sequence of action of these components of the hormonal hierarchy is:

Accepted Answer

A)  adrenal cortex $\rightarrow$ hypothalamus $\rightarrow$anterior pituitary. 
B)  anterior pituitary $\rightarrow$ adrenal cortex $\rightarrow$hypothalamus. 
C)  anterior pituitary $\rightarrow$ hypothalamus $\rightarrow$ adrenal cortex. 
D)  hypothalamus $\rightarrow$ adrenal cortex $\rightarrow$ anterior pituitary. 
E)  hypothalamus $\rightarrow$ anterior pituitary $\rightarrow$ adrenal cortex. 
A)  adrenal cortex $\rightarrow$ hypothalamus $\rightarrow$anterior pituitary. 
B)  anterior pituitary $\rightarrow$ adrenal cortex $\rightarrow$hypothalamus. 
C)  anterior pituitary $\rightarrow$ hypothalamus $\rightarrow$ adrenal cortex. 
D)  hypothalamus $\rightarrow$ adrenal cortex $\rightarrow$ anterior pituitary. 
E)  hypothalamus $\rightarrow$ anterior pituitary $\rightarrow$ adrenal cortex.

Question 10

Which statement does NOT describe a fate of amino acids in the liver?

Accepted Answer

A)  Amino acids are incorporated into new proteins. 
B)  Nitrogen equivalents from amino acids are converted to urea. 
C)  Carbon equivalents from amino acids are converted to glucose. 
D)  Amino acids are stored for later use. 
E)  Amino acids serve as precursors to nucleotide biosynthesis. 
A)  Amino acids are incorporated into new proteins. 
B)  Nitrogen equivalents from amino acids are converted to urea. 
C)  Carbon equivalents from amino acids are converted to glucose. 
D)  Amino acids are stored for later use. 
E)  Amino acids serve as precursors to nucleotide biosynthesis.

Question 11

Some hormones are derived from amino acids; for example, catecholamines are derived from _____ while NO is derived from _____.

Accepted Answer

A)  tyrosine; arginine 
B)  tryptophan; lysine 
C)  tyrosine; histidine 
D)  tryptophan; arginine 
E)  histidine; lysine 
A)  tyrosine; arginine 
B)  tryptophan; lysine 
C)  tyrosine; histidine 
D)  tryptophan; arginine 
E)  histidine; lysine

Question 12

Which class of hormones acts via nuclear receptors? Give an example of this type of hormone and briefly describe its mode of action.

Accepted Answer

Steroid hormones are a class of hormones

Question 13

Provide some distinguishing characteristics between eicosanoids and hormones such as epinephrine.

Accepted Answer

Eicosanoids and hormones such as epineph

Question 14

Which enzyme does NOT catalyze a substrate level phosphorylation reaction?

Accepted Answer

A)  ATP synthase 
B)  creatine kinase 
C)  pyruvate kinase 
D)  phosphoglycerate kinase 
E)  phosphoenoylpyruvate carboxykinase 
A)  ATP synthase 
B)  creatine kinase 
C)  pyruvate kinase 
D)  phosphoglycerate kinase 
E)  phosphoenoylpyruvate carboxykinase

Question 15

Glucokinase:

Accepted Answer

A)  acts in the conversion of liver glycogen to glucose 1-phosphate. 
B)  converts fructose-6-phosphate to glucose-6-phosphate 
C)  converts glucose 6-phosphate to fructose 6-phosphate. 
D)  is a hexokinase isozyme found in liver hepatocytes. 
E)  is found in all mammalian tissues. 
A)  acts in the conversion of liver glycogen to glucose 1-phosphate. 
B)  converts fructose-6-phosphate to glucose-6-phosphate 
C)  converts glucose 6-phosphate to fructose 6-phosphate. 
D)  is a hexokinase isozyme found in liver hepatocytes. 
E)  is found in all mammalian tissues.

Question 16

In a cell, the relative concentrations of ATP and ADP in the matrix ultimately control the rate of:

Accepted Answer

A)  glycolysis. 
B)  oxidative phosphorylation. 
C)  pyruvate oxidation. 
D)  both oxidative phosphorylation and pyruvate oxidation. 
E)  All of the answers are correct. 
A)  glycolysis. 
B)  oxidative phosphorylation. 
C)  pyruvate oxidation. 
D)  both oxidative phosphorylation and pyruvate oxidation. 
E)  All of the answers are correct.

Question 17

Which hormone triggers the release of $\alpha$-melanocyte-stimulating hormone from anorexigenic neurons?

Accepted Answer

A)  leptin 
B)  insulin 
C)  ghrelin 
D)  both leptin and insulin 
E)  both leptin and ghrelin 
A)  leptin 
B)  insulin 
C)  ghrelin 
D)  both leptin and insulin 
E)  both leptin and ghrelin

Question 18

What would likely be the consequence of a biochemical defect in which cortisol was secreted in excess?

Accepted Answer

A)  muscular weakness 
B)  diabetes 
C)  osteoporosis 
D)  All of the answers are correct. 
E)  None of the answers is correct. 
A)  muscular weakness 
B)  diabetes 
C)  osteoporosis 
D)  All of the answers are correct. 
E)  None of the answers is correct.

Question 19

What would likely be the consequence of a biochemical defect in which glucagon was secreted in excess?

Accepted Answer

A)  muscular fatigue due to lactic acidosis 
B)  inhibited glycolysis in the liver with depleted glycogen stores 
C)  lowered concentrations of ketone bodies circulating in the blood stream 
D)  depressed rate of urea excretion 
E)  excessive accumulation of triacylglycerols in adipocytes 
A)  muscular fatigue due to lactic acidosis 
B)  inhibited glycolysis in the liver with depleted glycogen stores 
C)  lowered concentrations of ketone bodies circulating in the blood stream 
D)  depressed rate of urea excretion 
E)  excessive accumulation of triacylglycerols in adipocytes

Question 20

Phenformin is a biguanide similar to metformin. It was used in the treatment of type 2 diabetes but was pulled from clinical use because it was associated with the potentially fatal side-effect of lactic acidosis. Provide a rational for this. (Hint: Biguanides enhance anaerobic metabolism.)

Accepted Answer

Phenformin, like metformin, is a biguani

Exam 23: Hormonal Regulation and Integration of Mammalian Metabolism

The LARGEST energy store in a well-nourished human is:

Each enzyme listed below catalyzes a reaction in the skeletal muscles of an Olympic sprinter. However, the role of which one would be considered LEAST significant during the running of a 100m sprint?

Describe five possible fates of amino acids arriving in the liver after intestinal uptake.

Which factor is NOT involved in triggering insulin from β\betaβ -cells release in response to glucose?

What explains the relative resistance to hypoglycemic coma in people who are starving compared with a normal person?

An example of a steroid hormone is:

Which statement describes one of the roles of mTORC1?

The hormone leptin _____ appetite; insulin _____ appetite.

The normal sequence of action of these components of the hormonal hierarchy is:

Which statement does NOT describe a fate of amino acids in the liver?

Some hormones are derived from amino acids; for example, catecholamines are derived from _____ while NO is derived from _____.

Which class of hormones acts via nuclear receptors? Give an example of this type of hormone and briefly describe its mode of action.

Provide some distinguishing characteristics between eicosanoids and hormones such as epinephrine.

Which enzyme does NOT catalyze a substrate level phosphorylation reaction?

Glucokinase:

In a cell, the relative concentrations of ATP and ADP in the matrix ultimately control the rate of:

Which hormone triggers the release of α\alphaα -melanocyte-stimulating hormone from anorexigenic neurons?

What would likely be the consequence of a biochemical defect in which cortisol was secreted in excess?

What would likely be the consequence of a biochemical defect in which glucagon was secreted in excess?

Phenformin is a biguanide similar to metformin. It was used in the treatment of type 2 diabetes but was pulled from clinical use because it was associated with the potentially fatal side-effect of lactic acidosis. Provide a rational for this. (Hint: Biguanides enhance anaerobic metabolism.)

The Foundations of Biochemistry

Water

Amino Acids, Peptides, and Proteins

The Three-Dimensional Structure of Proteins

Protein Function

Enzymes

Carbohydrates and Glycobiology

Nucleotides and Nucleic Acids

DNA-Based Information Technologies

Lipids

Biological Membranes and Transport

Biosignaling

Bioenergetics and Biochemical Reaction Types

Glycolysis, Gluconeogenesis, and the Pentose Phosphate Pathway

Principles of Metabolic Regulation

The Citric Acid Cycle

Fatty Acid Catabolism

Amino Acid Oxidation and the Production of Urea

Oxidative Phosphorylation and Photophosphorylation

Carbohydrate Biosynthesis in Plants and Bacteria

Lipid Biosynthesis

Biosynthesis of Amino Acids, Nucleotides, and Related Molecules

Genes and Chromosomes

DNA Metabolism

RNA Metabolism

Protein Metabolism

Regulation of Gene Expression

Filters

Which factor is NOT involved in triggering insulin from $\beta$ -cells release in response to glucose?

The hormone leptin _ appetite; insulin _ appetite.

Some hormones are derived from amino acids; for example, catecholamines are derived from _ while NO is derived from _.

Which hormone triggers the release of $\alpha$ -melanocyte-stimulating hormone from anorexigenic neurons?