Deck 7: Integration and Regulation of Metabolism and the Impact of Exercise

Question 1

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

Answer 1

B

Question 2

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

Answer 2

A

Question 3

In which organ does urea synthesis occur?

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

Answer 3

C

Question 4

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

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

Question 5

One of the regulated enzymes when glycolysis occurs is ____.

A)isocitrate dehydrogenase
B)pyruvate dehydrogenase
C)fructose-1,6-bisphosphatase
D)phosphofructokinase

Question 6

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

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

Question 7

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 8

The precursors for insulin's stimulation of fatty acid synthesis are excess ____.

A)sucrose and maltose
B)glucose and sucrose
C)fructose and sucrose
D)glucose and fructose

Question 9

When the cellular energy status favors anabolic reactions,pyruvate is converted to ____.

A)fructose
B)glucose
C)succinyl-CoA
D)NADPH

Question 10

What are the two compounds that connect the metabolism of carbohydrates,lipids,and proteins?

A)citrate and oxaloacetate
B)succinyl-CoA and malate
C)pyruvate and acetyl-CoA
D)CO₂ and NADPH

Question 11

An individual who has not eaten in five days will most likely have an elevated level of which hormone?

A)insulin
B)norepinephrine
C)glucagon
D)ACTH

Question 12

Which amino acid is considered purely ketogenic?

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

Question 13

Which of the following amino acids is glucogenic in the postabsorptive state?

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

Question 14

Skeletal muscle accounts for what percentage of protein turnover?

A)10-15%
B)15-20%
C)20-25%
D)25-35%

Question 15

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 16

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 17

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 18

In the human,most triacylglycerols are synthesized by the ____.

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

Question 19

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 20

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

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

Question 21

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

A)enhanced activity of glycolytic enzymes
B)fatty acid oxidation inhibiting glucose uptake and glycolysis
C)enhanced glucose uptake
D)decreased carnitine acyltransferase

Question 22

AMP-activated protein kinase (AMPK)controls both anabolic and catabolic pathways involving all ____.

A)macronutrients
B)fatty acids
C)micronutrients
D)amino acids

Question 23

An increase in glycolysis is accompanied by an increase in ____.

A)pyruvate dehydrogenase
B)isocitrate dehydrogenase
C)pyruvate kinase
D)fructose-1,6-bisphosphatase

Question 24

In humans,fatty acids cannot be used to synthesize glucose because we lack the enzymes needed to convert ____.

A)acetyl-CoA to lactate
B)glycogen to acyl-CoA
C)acetyl-CoA to pyruvate
D)acyl-CoA to acetyl-CoA

Question 25

The fed state of the fed-fast cycle lasts about how long and is characterized by secretion of which hormone?

A)1 hour/insulin
B)2 hours/insulin
C)3 hours/insulin
D)4 hours/insulin

Question 26

Citrate that moves from the mitochondria into the cytoplasm is converted by which enzyme into oxaloacetate and acetyl-CoA?

A)citrate lyase
B)citrate decarboxylase
C)citrate hydrogenase
D)citrate synthase

Question 27

A deficiency in carnitine acyltransferase I (CAT I)could lead to interference with ____.

A)glycolysis
B)gluconeogenesis
C)ATP production
D)CO₂ production

Question 28

Carbohydrate loading is a dietary and exercise strategy used to maximize ____.

A)glycogenolysis
B)glycolysis
C)lipolysis
D)glycogen storage in muscle and live

Question 29

What is the term used to represent maximum oxygen consumption relating to exercise capacity?

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

Question 30

Most nutrients absorbed by the small intestine first pass through the ____.

A)liver
B)pancreas
C)spleen
D)lymphatic system

Question 31

The majority of energy for ATP production is provided by dietary ____.

A)protein
B)protein and lipid
C)carbohydrate and protein
D)carbohydrate and lipid

Question 32

Which substances become the main fuel for high-intensity exercise lasting more than one hour?

A)plasma fatty acids
B)glucose and fructose
C)glycogen and glucose
D)ketone bodies

Question 33

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 34

Following a carbohydrate-rich meal,skeletal and cardiac muscle express which protein on their cell surfaces?

A)GLUT1
B)GLUT2
C)GLUT3
D)GLUT4

Question 35

After several weeks of starvation,what proportion of the energy needs of the brain is supplied by β-hydroxybutyrate and acetoacetate?

A)one-fourth
B)one-third
C)one-half
D)two-thirds

Question 36

The lactic acid system is also referred to as ____.

A)aerobic metabolism
B)anaerobic metabolism
C)aerobic glycolysis
D)anaerobic glycolysis

Question 37

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 38

The correct order of the pathway leading to glycogen production is ____.

A)pyruvate, alanine, glucose, glycogen
B)alanine, glucose, pyruvate, glycogen
C)pyruvate, glucose, alanine, glycogen
D)alanine, pyruvate, glucose, glycogen

Question 39

Which GLUT protein is the only one whose function is dependent on insulin?

A)GLUT1
B)GLUT2
C)GLUT3
D)GLUT4

Question 40

Malonyl-CoA plays a regulatory role in which two processes?

A)glycogenesis and gluconeogenesis
B)fatty acid synthesis and β-oxidation
C)glycolysis and protein degradation
D)gluconeogenesis and glycolysis

Question 41

When glucose exceeds the glycogen storage capacity of the liver,the excess glucose can be converted to ____.

A)acetyl-CoA
B)fructose
C)glucose-6-phosphate dehydrogenase
D)fatty acids and triacylglycerols

Question 42

Gluconeogenesis occurs exclusively in the liver.

Question 43

The Cori cycle would be active under anaerobic conditions,such as excessive muscle exertion.

Question 44

The metabolic fuel shifts associated with the starvation state are designed to spare body ____.

A)protein
B)carbohydrates
C)lipids
D)glycogen

Question 45

Time frames assigned to each of the phases of the fed-fast cycle are strongly influenced by an individual's ____.

A)metabolic rate
B)age
C)gender
D)ethnic background

Question 46

During the postabsorptive state,the major provider of glucose to the blood is ____.

A)hepatic glycolysis
B)hepatic glycogenolysis
C)renal gluconeogenesis
D)hepatic gluconeogenesis

Question 47

During very prolonged starvation nearing death,the body shifts from using protein for energy to using fat stores.

Question 48

Only the glycerol portion of triacylglycerols can be converted into ____.

A)fatty acids
B)alcohols
C)protein
D)carbohydrate

Question 49

The adipocytes of an individual with hypoglycemia would have difficulty producing ____

A)glycerol-3-phosphate
B)acetyl-CoA
C)acyl-CoA
D)glucose-6-phosphate dehydrogenase

Question 50

An individual with a deficiency of glycerol-3-phosphate would have difficulty synthesizing ____.

A)fatty acids
B)triacylglycerols
C)acetyl-CoA
D)glucose

Question 51

A fasted state is characterized by protein synthesis.

Question 52

Most regulatory enzymes act in a bidirectional manner.

Question 53

At rest,the brain uses what percentage of available energy?

A)5-10%
B)15-20%
C)20-25%
D)30-40%

Question 54

Fatty acids with an even number of carbons are degraded exclusively into ____.

A)glucose
B)fructose
C)acetyl-CoA
D)triacylglycerols

Question 55

Glucagon and insulin control metabolic pathways that reflect a fasting and fed state,respectively; the primary signal to initiate this hormonal control is the glucose concentration in the bloodstream.

Question 56

Acetyl-CoA is a junction point for a number of metabolic processes,including metabolism of carbohydrate,lipid,and cholesterol.

Question 57

The metabolic effects of glucagon occur in an effort to allow ATP production in the absence of dietary carbohydrate.

Question 58

Muscle and adipose tissue must obtain glycerol-3-phosphate through ____.

A)gluconeogenesis
B)glycolysis
C)glycogenolysis
D)glycogenesis

Question 59

All tissues prefer glucose first,and then fatty acids,to meet their energy needs.

Question 60

Muscle supplies its own glucose for energy needs by first using glycogen stores,and then converting amino acids to glucose.

Question 61

Define the two categories of metabolic pathways and explain the main purpose of each one.

Question 62

Pick two (2)of the examples from question 3 and indicate specifically how the signal you indicated in your answer is altering the pathway listed.For each example,write a one-sentence answer that includes the condition,the signals,the mechanism,the protein/enzyme,the tissue,and the result (all underlined in the example below).
Example: Under fed conditions,high blood glucose leads to insulin secretion by the pancreas,which in turn induces expression of the key glycolytic enzyme phosphofructokinase in all cells,thereby increasing glycolysis.

Question 63

[If students redraw the graph in Figure 7.12 here to show the relationship between these systems and their contribution to meeting energy needs as a function of time,that is fine as long as it was appropriately drawn,labeled,and explained.]
Name the three systems that play a role in supplying energy during movement/exercise.Describe briefly how they supply energy,and discuss the temporal relationship between them during prolonged exercise.Any figures should be completely labeled and explained.

Question 64

Match the regulatory hormones with their primary functions in integrative metabolism.
a.stimulates liver glycogenolysis and gluconeogenesis
b.stimulates lipolysis and increases triacylglycerol uptake from VLDL
c.stimulates gluconeogenesis and glycogenolysis in the liver
d.stimulates removal of glucose from the blood and anabolic reactions
e.produced from phenylalanine and tyrosine; functions as a neurotransmitter and a stress hormone
epinephrine

Question 65

The red color of muscle is due to the presence of myoglobin.

Question 66

The end products of the oxidative system are acetyl-CoA and glucose-6-phosphate dehydrogenase.

Question 67

Match the regulatory hormones with their primary functions in integrative metabolism.
a.stimulates liver glycogenolysis and gluconeogenesis
b.stimulates lipolysis and increases triacylglycerol uptake from VLDL
c.stimulates gluconeogenesis and glycogenolysis in the liver
d.stimulates removal of glucose from the blood and anabolic reactions
e.produced from phenylalanine and tyrosine; functions as a neurotransmitter and a stress hormone
growth hormone

Question 68

Most nutrients absorbed by the small intestine first pass through the liver.

Question 69

Metabolic pathways are regulated to maintain homeostasis in the face of changing environmental conditions,such as nutrient supply.Describe how this is accomplished during the fed-fast cycle,that is,the progression from a fed state,to a postabsorptive/fasting state,to starvation,to prolonged starvation.Your answer should include specific processes/ metabolic pathways that are favored under each condition-make sure to cover pathways that are important to all three macronutrients (CHOs,lipids,protein).Also indicate the signal(s)involved in modulating these pathways.An example is provided in the table.

Question 70

Match the metabolic activity to the correct organ.
a.relies solely on glucose for energy
b.fatty acids/glucose are the major fuel
c.stores large amounts of triacylglycerols
d.uses little glucose-6-phosphate and stores much glycogen
e.can adapt to using ketone bodies during prolonged energy deficit
muscle

Question 71

Match the regulatory hormones with their primary functions in integrative metabolism.
a.stimulates liver glycogenolysis and gluconeogenesis
b.stimulates lipolysis and increases triacylglycerol uptake from VLDL
c.stimulates gluconeogenesis and glycogenolysis in the liver
d.stimulates removal of glucose from the blood and anabolic reactions
e.produced from phenylalanine and tyrosine; functions as a neurotransmitter and a stress hormone
insulin

Question 72

Match the regulatory hormones with their primary functions in integrative metabolism.
a.stimulates liver glycogenolysis and gluconeogenesis
b.stimulates lipolysis and increases triacylglycerol uptake from VLDL
c.stimulates gluconeogenesis and glycogenolysis in the liver
d.stimulates removal of glucose from the blood and anabolic reactions
e.produced from phenylalanine and tyrosine; functions as a neurotransmitter and a stress hormone
glucagon

Question 73

Match the metabolic activity to the correct organ.
a.relies solely on glucose for energy
b.fatty acids/glucose are the major fuel
c.stores large amounts of triacylglycerols
d.uses little glucose-6-phosphate and stores much glycogen
e.can adapt to using ketone bodies during prolonged energy deficit
red blood cell

Question 74

Match the metabolic activity to the correct organ.
a.relies solely on glucose for energy
b.fatty acids/glucose are the major fuel
c.stores large amounts of triacylglycerols
d.uses little glucose-6-phosphate and stores much glycogen
e.can adapt to using ketone bodies during prolonged energy deficit
adipose tissue

Question 75

The postabsorptive state evolves into the fasting state after 36-72 hours of no food intake.

Question 76

Carbohydrate loading is a dietary and exercise strategy aimed at maximizing glycogenolysis in muscle and liver.

Question 77

Match the regulatory hormones with their primary functions in integrative metabolism.
a.stimulates liver glycogenolysis and gluconeogenesis
b.stimulates lipolysis and increases triacylglycerol uptake from VLDL
c.stimulates gluconeogenesis and glycogenolysis in the liver
d.stimulates removal of glucose from the blood and anabolic reactions
e.produced from phenylalanine and tyrosine; functions as a neurotransmitter and a stress hormone
cortisol

Question 78

Explain how endurance training increases an athlete's ability to perform more aerobically.

Question 79

Match the metabolic activity to the correct organ.
a.relies solely on glucose for energy
b.fatty acids/glucose are the major fuel
c.stores large amounts of triacylglycerols
d.uses little glucose-6-phosphate and stores much glycogen
e.can adapt to using ketone bodies during prolonged energy deficit
brain

Question 80

Match the metabolic activity to the correct organ.
a.relies solely on glucose for energy
b.fatty acids/glucose are the major fuel
c.stores large amounts of triacylglycerols
d.uses little glucose-6-phosphate and stores much glycogen
e.can adapt to using ketone bodies during prolonged energy deficit
liver