Deck 27: The Integration of Metabolism

Question 1

What is the major metabolic fuel for the brain after several days of starvation?

A) fatty acids
B) lactate
C) amino acids
D) ketone bodies
E) glycogen

Answer 1

D

Question 2

What metabolite,produced by adipose tissue,can only be metabolized in the liver?

A) $\beta$ -hydroxybutyrate
B) arachidonic acid
C) acetone
D) cholesterol
E) glycerol

Answer 2

glycerol

Question 3

When levels of ketone bodies are high,the _________________ can no longer maintain acid-base balance in the blood.

Answer 3

kidney

Question 4

What fuel is used exclusively by muscles following a day of starvation?

A) glycogen
B) fatty acids
C) alanine
D) glucose
E) $\beta$ -hydroxybutyrate

Question 5

Except under rare conditions,what organ is almost exclusively reliant on glucose for energy?

A) brain
B) liver
C) small intestine
D) heart
E) kidney

Question 6

The microsomal ethanol-oxidizing system (MEOS)consumes oxygen and ______________,which leads to oxidative stress partly due to the inability to regenerate glutathione.

Question 7

ATP production from ___________________ is essential for long-distance running.

Question 8

The dehydrogenase metabolism of ethanol leads to an excess production of ________________ in addition to acetyl CoA.

Question 9

What type of tissue stores the bulk (by total mass)of the body's glycogen?

A) liver
B) heart
C) brain
D) pancreas
E) muscle

Question 10

What hormone,released by the small intestine,generates a sense of satiation and inhibits appetite?

A) leptin
B) cholecystokinin
C) glucagon
D) insulin
E) None of the answers is correct.

Question 11

Glycolysis and gluconeogenesis are usually _________________ regulated.

Question 12

When running a marathon,fuel sources from ___________________,muscle,and adipose are used.

Question 13

In addition to fatty acids,what molecule is needed by adipose tissue to synthesize triacylglycerols?

A) acetyl CoA
B) alanine
C) $\beta$ -hydroxybutyrate
D) glucose
E) None of the answers is correct.

Question 14

Which organ is considered to be the metabolic "hub" of the body?

A) brain
B) small intestine
C) liver
D) pancreas
E) adipose tissue

Question 15

The primary target organ of glucagon is the ___________________.

Question 16

What hormone stimulates glycogen breakdown and gluconeogenesis?

A) leptin
B) cholecystokinin
C) glucagon
D) insulin
E) ghrelin

Question 17

____________________ results when insulin is absent due to autoimmune destruction of the β cells of the pancreas.

Question 18

What hormone,released by adipose tissue,generates a sense of satiation and inhibits the appetite?

A) leptin
B) cholecystokinin
C) neuropeptide Y
D) insulin
E) None of the answers is correct.

Question 19

Obesity is defined as a BMI of greater than________________________.

Question 20

The "fed state" leads to the release of the hormone ____________________.

Question 21

Which of the following occurs in the pancreatic β cell when blood glucose levels increase?

A) Insulin is secreted by receptor-mediated endocytosis.
B) Intracellular ATP/ADP levels increase.
C) K⁺ channels open, altering the membrane potential.
D) Ca²⁺ channels close.
E) All of the above occur.

Question 22

GLP-1 triggers which of the following in the brain?

A) decreased satiety
B) decreased food intake
C) decreased body weight
D) All of the answers are correct.
E) decreased food intake and decreased body weight

Question 23

Excess alcohol consumption can lead to Wernicke-Korsaff syndrome due to the lack of the vitamin thiamine.Which of the following metabolic conversions CANNOT occur in the absence of thiamine?

A) pyruvate + CO₂ $\rarr$ oxaloacetate
B) pyruvate $\rarr$ acetyl-CoA + CO₂
C) $\alpha$ -ketoglutarate $\rarr$ succinyl-CoA + CO₂
D) phosphoenolpyruvate + CO₂ $\rarr$ oxaloacetate
E) B and C are correct.

Question 24

What are the fuels used in a long distance run?

A) creatine phosphate
B) liver glycogen
C) muscle glycogen
D) fatty acids
E) All of the answers are correct.

Question 25

The primary function of aerobic glycolysis is to

A) degrade glucose to provide ATP.
B) provide carbon skeletons for biosynthesis.
C) provide NADH for lactate reduction.
D) provide NADPH for biosynthetic reactions
E) None of the answers is correct.

Question 26

Show how the metabolism of the liver and skeletal muscle is interconnected by blood glucose and alanine during strenuous exercise.

Question 27

Maintenance of a constant blood-glucose level is called

A) glucose tolerance.
B) glucose adjustment.
C) glucose homeostasis.
D) cholecystokinin.
E) None of the answers is correct.

Question 28

What is the primary source of energy used by the muscle during starvation?

A) glucose
B) lactate
C) fatty acids
D) ketone bodies
E) branched-chain amino acids

Question 29

What are the two factors that have led to a propensity to gain weight in humans,and how can they be negated?

Question 30

Which of the following metabolic conversions provides the maximum rate of ATP production (mmol sec^-1)for muscle contraction?

A) muscle glycogen to CO₂
B) muscle glycogen to lactate
C) creatine phosphate and ADP to ATP and creatine
D) fatty acid to CO₂
E) liver glycogen to CO₂

Question 31

The First Law of Thermodynamics translated into dietary terms can be stated as

A) energy expended = energy consumed + energy stored.
B) potential energy = energy consumed + energy expended.
C) energy consumed = energy expended + energy stored.
D) kinetic energy = energy consumed + energy stored.

Question 32

What is the key regulatory enzyme in glycolysis?

A) phosphofructokinase
B) glucokinase
C) hexokinase
D) triose phosphate isomerase
E) None of the answers is correct.

Question 33

What is the advantage of converting pyruvate to lactate in skeletal muscle?

Question 34

Identify and describe the two signals from the gastrointestinal tract that induce feelings of satiety.

Question 35

In a typical human male,which of the following most closely approximates the energy content (in kcal)of triacylglycerols stored in adipose tissue?

A) 13,500 kcal
B) 135,000 kcal
C) 1,350,000 kcal
D) 13,500 cal
E) None of the answers is correct.

Question 36

Which of the following is the primary fuel used by the brain during starvation?

A) ketone bodies
B) glucose derived from glycogen
C) amino acids
D) branched chain amino acids
E) fatty acids

Question 37

Health consequences of obesity may include

A) coronary heart disease.
B) hypertension.
C) stroke.
D) type II diabetes.
E) All the answers are correct.

Question 38

Insulin signals the ______ state,and glucagon signals the _______ state.

A) fed; starved
B) starved; fed
C) fed; maintenance
D) maintenance; fed
E) starved; maintenance

Question 39

What are the three primary sources of glucose 6-phosphate in liver cells?

Question 40

The ___________ is/are an important source of metabolites for gluconeogenesis during starvation.

A) kidney
B) brain
C) intestine
D) muscle
E) red blood cells

Question 41

What is the cause of type 1 diabetes?

Question 42

What are some of the primary metabolic fates of acetyl CoA in animals?

Question 43

What is the major fuel for resting muscle,and what it the major fuel for muscle under strenuous work conditions?

Question 44

Describe how low glucose levels can decrease triacylglycerol synthesis in adipose tissue.

Question 45

Explain what is meant by the term the starved-fed cycle.What are the stages?

Question 46

What are the plasma concentrations of glucose in the normal fasting and starvation states?

Question 47

Describe the stages of ethanol consumption that affect liver damage and lead to death.

Question 48

What are the two hypotheses supporting low-carbohydrate-high-protein diets as an effective weight losing strategy?

Question 49

How do SOCS (suppressors of cytokine signaling)proteins inhibit receptor signaling? Give one example.

Question 50

What metabolic changes occur during the early fasting state?