Question 1

The Cori cycle is the:

Accepted Answer

A)  conversion of lactate to pyruvate in skeletal muscle to drive glycogen synthesis. 
B)  interconversion between glycogen and glucose l-phosphate. 
C)  production of lactate from glucose in peripheral tissues with the resynthesis of glucose from lactate in liver. 
D)  synthesis of alanine from pyruvate in skeletal muscle and the synthesis of pyruvate from alanine in liver. 
E)  synthesis of urea in liver and degradation of urea to carbon dioxide and ammonia by bacteria in the gut. 
A)  conversion of lactate to pyruvate in skeletal muscle to drive glycogen synthesis. 
B)  interconversion between glycogen and glucose l-phosphate. 
C)  production of lactate from glucose in peripheral tissues with the resynthesis of glucose from lactate in liver. 
D)  synthesis of alanine from pyruvate in skeletal muscle and the synthesis of pyruvate from alanine in liver. 
E)  synthesis of urea in liver and degradation of urea to carbon dioxide and ammonia by bacteria in the gut.

Question 2

A major difference between white adipose tissue and brown adipose tissue is that only:

Accepted Answer

A)  white adipose tissue stores fatty acids as triacylglycerols. 
B)  brown adipose tissue degrades fatty acids via the citric acid cycle. 
C)  brown adipose tissue contains thermogenin. 
D)  white adipose tissue contains adipocytes. 
E)  white adipose tissue responds to hormone signals. 
A)  white adipose tissue stores fatty acids as triacylglycerols. 
B)  brown adipose tissue degrades fatty acids via the citric acid cycle. 
C)  brown adipose tissue contains thermogenin. 
D)  white adipose tissue contains adipocytes. 
E)  white adipose tissue responds to hormone signals.

Question 3

Covalent modification via phosphorylation/dephosphorylation of specific key enzymes modifies their catalytic activity, and thus the flux through pathways. Which pathway below is NOT regulated by this strategy?

Accepted Answer

A)  cholesterol synthesis in the liver 
B)  lipolysis in adipocytes 
C)  glycogen degradation in skeletal muscle 
D)  fatty acid synthesis in the liver 
E)  esterification to form triacylglycerols in the liver 
A)  cholesterol synthesis in the liver 
B)  lipolysis in adipocytes 
C)  glycogen degradation in skeletal muscle 
D)  fatty acid synthesis in the liver 
E)  esterification to form triacylglycerols in the liver

Question 4

Which hormone must bind to a plasma membrane receptor before it has an effect?

Accepted Answer

A)  cortisol 
B)  retinoic acid 
C)  nitric oxide 
D)  norepinephrine 
E)  thyroxine 
A)  cortisol 
B)  retinoic acid 
C)  nitric oxide 
D)  norepinephrine 
E)  thyroxine

Question 5

Epinephrine is an example of a(n) _____ hormone.

Accepted Answer

A)  catecholamine 
B)  eicosanoid 
C)  paracrine 
D)  peptide 
E)  steroid 
A)  catecholamine 
B)  eicosanoid 
C)  paracrine 
D)  peptide 
E)  steroid

Question 6

Which statement is TRUE?

Accepted Answer

A)  The brain prefers glucose as an energy source, but can use ketone bodies. 
B)  Muscle cannot use fatty acids as an energy source. 
C)  In a well-fed human, about equal amounts of energy are stored as glycogen and as triacylglycerol. 
D)  Fatty acids cannot be used as an energy source in humans because humans lack the enzymes of the glyoxylate cycle. 
E)  Amino acids are a preferable energy source over fatty acids. 
A)  The brain prefers glucose as an energy source, but can use ketone bodies. 
B)  Muscle cannot use fatty acids as an energy source. 
C)  In a well-fed human, about equal amounts of energy are stored as glycogen and as triacylglycerol. 
D)  Fatty acids cannot be used as an energy source in humans because humans lack the enzymes of the glyoxylate cycle. 
E)  Amino acids are a preferable energy source over fatty acids.

Question 7

Which protein is inhibited by insulin?

Accepted Answer

A)  glucokinase 
B)  GLUT4 
C)  acetyl-CoA carboxylase 
D)  pyruvate dehydrogenase 
E)  glycogen phosphorylase 
A)  glucokinase 
B)  GLUT4 
C)  acetyl-CoA carboxylase 
D)  pyruvate dehydrogenase 
E)  glycogen phosphorylase

Question 8

In skeletal muscle, phosphocreatine functions as:

Accepted Answer

A)  a reservoir of Pi for mitochondria. 
B)  reservoir of high-energy of phosphate to replenish ATP. 
C)  reservoir of amino acids for protein synthesis. 
D)  an electron acceptor under anaerobic conditions. 
E)  None of the answers is correct. 
A)  a reservoir of Pi for mitochondria. 
B)  reservoir of high-energy of phosphate to replenish ATP. 
C)  reservoir of amino acids for protein synthesis. 
D)  an electron acceptor under anaerobic conditions. 
E)  None of the answers is correct.

Question 9

Briefly explain the role of phosphocreatine in muscle.

Accepted Answer

Phosphocreatine, also known as creatine

Question 10

An example of an eicosanoid 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 11

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

Accepted Answer

A)  Fatty acids are oxidized to generate ATP. 
B)  Fatty acids are converted to ketone bodies. 
C)  Fatty acids can be converted to cholesterol. 
D)  Fatty acids are stored for later use. 
E)  Fatty acids are converted to glucose. 
A)  Fatty acids are oxidized to generate ATP. 
B)  Fatty acids are converted to ketone bodies. 
C)  Fatty acids can be converted to cholesterol. 
D)  Fatty acids are stored for later use. 
E)  Fatty acids are converted to glucose.

Question 12

Which consequence is MOST likely following the ingestion of ethanol after a heavy physical workout?

Accepted Answer

A)  enhanced uptake of lactate by liver 
B)  gluconeogenesis will be inhibited in hepatocytes 
C)  glycogen synthesis will be stimulated in hepatocytes 
D)  secretion of glucagon will be inhibited 
E)  None of the answers is correct. 
A)  enhanced uptake of lactate by liver 
B)  gluconeogenesis will be inhibited in hepatocytes 
C)  glycogen synthesis will be stimulated in hepatocytes 
D)  secretion of glucagon will be inhibited 
E)  None of the answers is correct.

Question 13

Which statement is TRUE regarding the late stages of starvation?

Accepted Answer

A)  The brain has decreased its need for glucose by switching to lactate as a major energy source. 
B)  High levels of acetyl-CoA derived from lipid catabolism lead to the production of acetoacetate. 
C)  Ketone bodies are produced from amino acids liberated from noncritical proteins. 
D)  Gluconeogenesis is extremely active in the liver because of the large amounts of lactate exported from the muscle. 
E)  Catabolism of triacylglycerols provides the major source of a gluconeogenic metabolite in the form of glycerol. 
A)  The brain has decreased its need for glucose by switching to lactate as a major energy source. 
B)  High levels of acetyl-CoA derived from lipid catabolism lead to the production of acetoacetate. 
C)  Ketone bodies are produced from amino acids liberated from noncritical proteins. 
D)  Gluconeogenesis is extremely active in the liver because of the large amounts of lactate exported from the muscle. 
E)  Catabolism of triacylglycerols provides the major source of a gluconeogenic metabolite in the form of glycerol.

Question 14

The maturation of insulin from its precursor (preproinsulin) involves:

Accepted Answer

A)  acetylation. 
B)  oxidation. 
C)  phosphorylation. 
D)  proteolysis. 
E)  reduction. 
A)  acetylation. 
B)  oxidation. 
C)  phosphorylation. 
D)  proteolysis. 
E)  reduction.

Question 15

What is a major problem in isolating a new hormone once a bioassay has been developed?

Accepted Answer

A major problem in isolating a new hormo

Question 16

The tropic hormones (such as thyrotropin, somatotropin, and luteinizing hormone) are produced and released by the:

Accepted Answer

A)  anterior pituitary. 
B)  hypothalamus. 
C)  ovaries. 
D)  pancreas. 
E)  posterior pituitary. 
A)  anterior pituitary. 
B)  hypothalamus. 
C)  ovaries. 
D)  pancreas. 
E)  posterior pituitary.

Question 17

Some hormones trigger very rapid responses, whereas for others the response takes much longer to develop. What generalization about the mechanisms of action of these two types of hormones can explain the differences in response times?

Accepted Answer

The differences in response times to hor

Question 18

Elevated epinephrine levels do not normally stimulate:

Accepted Answer

A)  fatty acid mobilization in adipose tissue. 
B)  gluconeogenesis in liver. 
C)  glycogen breakdown in muscle. 
D)  glycogen synthesis in liver. 
E)  glycolysis in muscle. 
A)  fatty acid mobilization in adipose tissue. 
B)  gluconeogenesis in liver. 
C)  glycogen breakdown in muscle. 
D)  glycogen synthesis in liver. 
E)  glycolysis in muscle.

Question 19

Describe the signaling cascade initiated by leptin binding to its receptor.

Accepted Answer

Leptin is a hormone that plays a key rol

Question 20

Which signal is required for mTORC1 activation?

Accepted Answer

A)  branched-chain amino acids 
B)  nutrient availability 
C)  energy resources 
D)  certain growth factors 
E)  All of the answers are correct. 
A)  branched-chain amino acids 
B)  nutrient availability 
C)  energy resources 
D)  certain growth factors 
E)  All of the answers are correct.

Exam 23: Hormonal Regulation and Integration of Mammalian Metabolism

The Cori cycle is the:

A major difference between white adipose tissue and brown adipose tissue is that only:

Covalent modification via phosphorylation/dephosphorylation of specific key enzymes modifies their catalytic activity, and thus the flux through pathways. Which pathway below is NOT regulated by this strategy?

Which hormone must bind to a plasma membrane receptor before it has an effect?

Epinephrine is an example of a(n) _____ hormone.

Which statement is TRUE?

Which protein is inhibited by insulin?

In skeletal muscle, phosphocreatine functions as:

Briefly explain the role of phosphocreatine in muscle.

An example of an eicosanoid hormone is:

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

Which consequence is MOST likely following the ingestion of ethanol after a heavy physical workout?

Which statement is TRUE regarding the late stages of starvation?

The maturation of insulin from its precursor (preproinsulin) involves:

What is a major problem in isolating a new hormone once a bioassay has been developed?

The tropic hormones (such as thyrotropin, somatotropin, and luteinizing hormone) are produced and released by the:

Some hormones trigger very rapid responses, whereas for others the response takes much longer to develop. What generalization about the mechanisms of action of these two types of hormones can explain the differences in response times?

Elevated epinephrine levels do not normally stimulate:

Describe the signaling cascade initiated by leptin binding to its receptor.

Which signal is required for mTORC1 activation?

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