Deck 7: Integration and Regulation of Metabolismand the Impact of Exercise and Sport

Question 1

Which hormone has the primary responsibility for directing energy metabolism in the fed state?

A) growth hormone
B) ACTH
C) glucagon
D) insulin

Answer 1

D

Question 2

Which of the following is NOT transported by the vascular system?

A) regulatory hormonal messages from the endocrine system
B) oxygen from the respiratory system
C) regulatory neural messages from the nervous system
D) organic nutrients and minerals from the digestive system

Answer 2

C

Question 3

How long does it take for the postabsorptive state to evolve into the fasting state?

A) 12-18 hours
B) 24-36 hours
C) 18-48 hours
D) 36-72 hours

Answer 3

C

Question 4

A protein-sparing shift in metabolism from gluconeogenesis to lipolysis occurs during the

A) early fasting state.
B) fasting state.
C) starvation state.
D) fed state.

Question 5

What is the primary communication system that assesses the body's status in relation to its environment and relays appropriate commands to tissues/ organs?

A) endocrine system
B) nervous system
C) vascular system
D) respiratory system

Question 6

In the human, most triacylglyerols are synthesized by the

A) adipose tissue.
B) heart.
C) liver.
D) brain.

Question 7

Which cells lack a metabolic mechanism to convert glucose into energy stores?

A) skeletal muscle
B) liver
C) adipose tissue
D) central nervous system

Question 8

What is the final common catabolic pathway for metabolism of carbohydrate, protein, and fat?

A) acetyl-CoA; oxidation
B) gluconeogenesis; glycolysis
C) Krebs cycle; electron transport
D) lipolysis; ketogenesis

Question 9

Amino acids from muscle breakdown provide the chief substrate for which metabolic process?

A) glycolysis
B) gluconeogenesis
C) glycogenesis
D) pentose phosphate pathway

Question 10

Under the influence of insulin, which of the following pathways is increased?

A) glycogenesis
B) glycogenolysis
C) phosphorylation of glycogen synthase
D) phosphorylation of glycogen phosphorylase

Question 11

What amino acid plays an important role in controlling toxicity from ammonia released during amino acid catabolism by the glutamate dehydrogenase reaction?

A) glutamine
B) glycine
C) serine
D) valine

Question 12

The brain cannot use fatty acids for energy because

A) it lacks enzymes for oxidation of fats.
B) it lacks mitochondria.
C) glycerol cannot cross the blood-brain barrier.
D) fatty acids cannot cross the blood-brain barrier.

Question 13

Which amino acid is considered purely ketogenic?

A) methionine
B) histidine
C) tryptophan
D) leucine

Question 14

Amino acids used primarily by muscle for synthesis of dispensable amino acids and for protein synthesis are

A) branched-chain amino acids.
B) aromatic amino acids.
C) basic amino acids.
D) acidic amino acids.

Question 15

What intermediate's formation in the Krebs cycle is interrelated with the biosynthesis of heme?

A) succinyl-CoA
B) oxaloacetate
C) citrate
D) fumarate

Question 16

The lack of which muscle enzyme causes glucose, when phosphorylated in the muscle, to be trapped?

A) glucose-6-phosphatase
B) glycerol-3-phosphatase
C) 6-phosphoglycerate dehydrogenase
D) glucokinase

Question 17

Which of the following amino acids is glucogenic in the post-absorptive state?

A) taurine
B) leucine
C) alanine
D) lysine

Question 18

In which organ does urea synthesis occur?

A) kidney
B) spleen
C) liver
D) pancreas

Question 19

Which amino acid produced by transamination of pyruvate with glutamic acid provides a disposal route for nitrogen produced from the catabolism of muscle amino acids?

A) histidine
B) tyrosine
C) tryptophan
D) alanine

Question 20

Which Krebs cycle intermediate can move from the mitochondria into the cytoplast to become the initiator of fatty acid synthesis?

A) alpha-ketoglutarate
B) citrate
C) succinyl-CoA
D) fumarate

Question 21

In the fasted state, you would find:

A) dephosphorylated glycogen synthase.
B) an increase in the amount of hexokinase.
C) allosteric inhibition of phosphofructokinase by NAD.
D) induction of pyruvate carboxylase.
E) more than one of the above

Question 22

The primary stimulus for glucagon secretion is

A) alanine.
B) glucose.
C) cortisol.
D) epinephrine.

Question 23

During exercise, which of the following contributes only minimally to the amount of ATP used by working muscles?

A) muscle glycogen
B) blood glucose
C) plasma fatty acids
D) oxidation of amino acids

Question 24

After three days of starvation, what proportion of the energy needs of the brain is supplied by ketones?

A) one-eighth
B) one-fourth
C) one-third
D) one-half

Question 25

What is the term used to describe the intensity of the workload that places the highest possible demand on working muscles?

A) respiratory quotient
B) VO₂ max
C) ATP-CP
D) lactic acid system

Question 26

What is the limitation that shifts the predominant use of fat for energy at low-intensity exercise to the predominant use of carbohydrate oxidation at high-intensity exercise?

A) rate of production of ATP
B) rate of mobilization of fatty acids from the adipocytes
C) rate of transamination of amino acids
D) rate of muscle glycogen breakdown

Question 27

If someone consumes a high-protein diet to meet energy needs, he/she will use _____ oxygen relative to the amount of CO₂ he/she is generating (Hint: think RQ).

A) less
B) more
C) equal
D) not enough information

Question 28

What is the preferred source of energy used by muscles to spare protein during prolonged starvation?

A) ketones
B) glucose
C) fatty acids
D) amino acids

Question 29

Which of the following conditions is attributed to a primary failure of the β-cells of the pancreas to secrete insulin?

A) hyperinsulinism
B) hyperglycemia
C) hyperlipidemia
D) hyperphosphatemia

Question 30

Training enhances utilization of fat as the primary energy substrate during submaximal exercise due to

A) enhanced activity of glycolytic enzymes.
B) enhanced activity of mitochondrial oxidative enzymes.
C) enhanced glucose uptake.
D) decreased carnitine acyltransferase.

Question 31

Which of the following actions of insulin occurs only after hours or days?

A) membrane changes for glucose transport
B) inhibition of activity of catabolic enzymes
C) repression of synthesis of catabolic enzymes
D) promotion of cell replication