Deck 16: Regulation of Organic Metabolism and Energy Balance

Question 1

Which is TRUE regarding chylomicrons?

A)They readily cross the plasma membrane of adipose cells.
B)They are converted to monoglycerides and fatty acids by an enzyme inside muscle cells.
C)They are converted to monoglycerides and fatty acids by an enzyme found inside capillaries.
D)They are formed in the lumen of the GI tract by the action of bile salts.
E)They are too large to enter lacteals.

Answer 1

C

Question 2

When plasma glucose concentration increases,the secretion of insulin is ________ and the secretion of glucagon is ________.However,an increase in sympathetic activity will cause ________ secretion of insulin and ________ secretion of glucagon.

A)decreased; increased; increased; decreased
B)increased; decreased; decreased; increased
C)increased; decreased; increased; decreased
D)increased; increased; decreased; increased
E)decreased; decreased; increased; unchanged

Answer 2

B

Question 3

Which correctly describes an action of the hormone insulin?

A)It increases the uptake and utilization of glucose by muscle and adipose tissue cells.
B)It is required for the uptake and utilization of glucose by nervous tissue.
C)It decreases the uptake of amino acids by muscle cells.
D)It stimulates the breakdown of glycogen in the liver.
E)It inhibits the action of lipoprotein lipase in the capillaries of adipose tissue.

Answer 3

A

Question 4

During the absorptive state of metabolism,

A)Liver glycogen is broken down to glucose,which is released into the blood.
B)Glycogen in muscle cells is broken down to glucose,which is used for energy.
C)Lipoprotein lipase breaks down triacylglycerols in adipose tissue capillaries.
D)Fatty acids and glycerol are released from adipose tissue.
E)Lactate and pyruvate secretion into the bloodstream by the muscles increases.

Question 5

Which of the following tissues is most dependent upon a constant blood supply of glucose?

A)liver
B)brain
C)adipose
D)skeletal muscle
E)cardiac muscle

Question 6

Dietary amino acids in a meal that are in excess of the body's need to make protein are:

A)converted to glucose in the liver.
B)converted to fatty acids in the liver.
C)excreted without being absorbed.
D)converted to fatty acids in adipiose cells.
E)burned for fuel by cells of the nervous system.

Question 7

During the absorptive state of metabolism,the primary energy source for most of the body's cells is ________,except for ________,which use ________ for energy.

A) amino acids; brain cells; glucose
B) fatty acids; brain cells; glucose
C) glucose; liver cells; amino acids
D) glucose; liver cells; ketones
E) fatty acids; skeletal muscle cells; glucose

Question 8

Glucagon secretion is stimulated by:

A)hypoglycemia and parasympathetic nerve firing.
B)hyperglycemia and a high concentration of epinephrine.
C)high plasma epinephrine and high plasma incretin concentrations.
D)hypoglycemia and high plasma epinephrine concentration.
E)hyperglycemia and high plasma incretin concentration.

Question 9

What enzyme converts chylomicron triacylglycerols into fatty acids and monoglycerides?

A)pancreatic lipase
B)pancreatic amylase
C)lipoprotein lipase
D)pepsin
E)hexokinase

Question 10

Which of the following occurs following absorption of glucose?

A)Glucose is stored as fat in skeletal muscle.
B)Glucose is stored as glycogen in adipose tissue.
C)Glucose is converted to fat in the liver.
D)Glucose is used to make energy by only the brain.
E)Glucose is converted to amino acids in the muscles.

Question 11

Which results from insulin binding to its receptor in skeletal muscle plasma membranes?

A)Glycogen synthase is stimulated.
B)Glycogen phosphorylase is stimulated.
C)Lipoprotein lipase is inhibited.
D)Glucose transport into the cell is inhibited.
E)Protein catabolism is stimulated.

Question 12

Which of the following does NOTcharacterize the postabsorptive state?

A)hyperglycemia occurs
B)gluconeogenesis occurs
C)glucose-sparing reactions occur
D)insulin secretion is lower than in the absorptive state
E)glucagon secretion is higher than in the absorptive state

Question 13

After absorbing nutrients in the intestines,blood then travels to:

A)the liver which metabolizes many of the absorbed nutrients.
B)the right atrium via the vena cava.
C)the abdominal aorta for distribution to the tissues.
D)the spleen so any ingested microbes can be destroyed.

Question 14

With regard to fat metabolism,insulin increases:

A)the activity of lipoprotein lipase,which catabolizes triglycerides.
B)the activity of hormone-sensitive lipase,which synthesizes triglycerides.
C)the activity of hormone-sensitive lipase,which catabolizes triglycerides.
D)the activity of lipoprotein lipase,which increases triglyceride synthesis.
E)the export of fatty acids and mononglyceride from adipocytes.

Question 15

Which of the following is a major metabolic effect of glucagon?

A)increased glucose uptake by muscle cells
B)increased triglyceride synthesis in adipose
C)decreased glycogenolysis in muscle
D)decreased gluconeogenesis in liver
E)increased glycogenolysis in liver

Question 16

Which of the following is NOTa fate of absorbed glucose?

A)It is converted to glycogen by liver cells.
B)It is converted to fatty acids and alpha-glycerol phosphate in adipose cells.
C)It is converted to glycogen in muscle cells.
D)It is converted to urea by liver cells.
E)It is converted to fatty acids and alpha glycerol phosphate by liver cells.

Question 17

The major metabolic effects of glucagon include:

A)stimulating glycogenolysis and gluconeogenesis in the liver.
B)stimulating triglyceride synthesis in adipose tissue.
C)stimulating glucose uptake into skeletal muscle cells.
D)stimulating the activity of glycogen synthase in the liver.
E)inhibiting the enzyme glycogen phosphorylase in the liver.

Question 18

Excess absorbed glucose is initially converted to triacylglycerides and very low density lipoprotein by:

A)adipose cells.
B)liver cells.
C)intestinal mucosa cells.
D)muscle cells.
E)lymphoid cells.

Question 19

During the postabsorptive phase of metabolism:

A)glycogen in muscle cells is broken down to glucose,which is released into the blood.
B)liver glycogen is broken down to glucose,which is released into the blood.
C)triacylglycerols in adipose tissue are broken down to glucose by lipolysis.
D)the liver exports lactate to the muscles,which use it for fuel.
E)glycerol and fatty acids are rapidly assembled into triglycerides in adipose tissue.

Question 20

During the absorptive state of metabolism,amino acids:

A)are used for protein synthesis in most body cells.
B)are used for glycogen synthesis in the liver.
C)may be converted to fat or glucose in the liver.
D) are burned as fuel in muscles,creating urea as a waste product.
E)are mobilized from muscle and other tissues faster than they are taken up by those tissues.

Question 21

During fasting,ketones produced by the liver:

A)are a waste product of amino acid metabolism that the kidneys must excrete.
B)can be used by the brain as an energy source.
C)are a by-product of anaerobic metabolism.
D)are converted to fatty acids and released into the blood.
E)are used to synthesize glucose by gluconeogenesis.

Question 22

During exercise:

A)blood glucose levels fall dramatically.
B)epinephrine and glucagon stimulate glycogenolysis in liver cells
C)decreased blood glucose and increased epinephrine stimulate insulin secretion.
D)epinephrine stimulates glucagon secretion and inhibits skeletal muscle uptake of glucose.
E)cortisol and growth hormone secretion are decreased.

Question 23

In untreated type 1 diabetes mellitus (insulin-dependent diabetes mellitus),acidosis occurs because:

A)dehydration concentrates the blood so even though H⁺ production is normal,its concentration is high.
B)kidney failure results in a decreased ability to excrete the normal amount of H⁺.
C)excess plasma glucose is taken up by the liver and converted to fatty acids.
D)insulin levels are extremely high,and insulin is an acidic protein hormone.
E)excessive lipolysis results in increased plasma fatty acid levels,which the liver converts to acidic ketones.

Question 24

Which of the following would increase gluconeogenesis?

A)increased plasma insulin levels
B)increased plasma incretin levels
C)increased plasma cortisol levels
D)decreased plasma growth hormone levels
E)decreased plasma glucagon levels

Question 25

Which of these is found in chylomicrons and plasma membranes,and is a precursor for bile salts and steroid hormones?

A)amino acids
B)cholesterol
C)phospholipids
D)monoglycerides
E)protein

Question 26

Which is NOT stimulated by the hormone insulin?

A)an increase in the number of glucose transporters in cell membranes
B)an increase in amino acid uptake by cells
C)an increase in glycogen synthesis
D)an increase in triglyceride synthesis
E)an increase in ketone synthesis

Question 27

In subjects with Type 2 (non-insulin-dependent)diabetes mellitus,which of these occurs?

A)Pancreatic beta cell responses to increased plasma glucose concentration are normal.
B)Target tissues have fewer than normal insulin receptors or defective insulin receptors.
C)Pancreatic beta cells are unable to secrete insulin.
D)Hypoglycemia is typically the first symptom.
E)Pancreatic alpha cells hypersecrete glucagon.

Question 28

Which would NOT be a characteristic of a person with untreated type I diabetes mellitus?

A)decreased glycogen stores in muscles
B)increased hemoglobin glycosylation
C)decreased blood pH
D)increased urination frequency
E)decreased thirst

Question 29

Which of the following is most descriptive of a state of prolonged fasting?

A)The secretion of insulin,glucagon,ACTH,and cortisol would all be increased.
B)Brain metabolism will shift to increase utilization of glucose and to decrease oxidation of ketones.
C)Muscle protein will be broken down to provide substrates for hepatic and renal gluconeogenesis.
D)The secretion of insulin,glucagon,ACTH,and cortisol will all be decreased.
E)The secretion of insulin and cortisol would be increased,while glucagon and ACTH secretion would be decreased.

Question 30

Which of the following leads to an increase in the ratio of LDL cholesterol : HDL cholesterol?

A)estrogen
B)cigarette smoking
C)exercise
D)weight reduction
E)All of these increase the LDL:HDL ratio.

Question 31

Which accurately describes the metabolic actions of cortisol during fasting?

A)It decreases blood glucose by increasing the sensitivity of muscle and adipose to insulin.
B)It stimulates protein synthesis in muscle cells,and is permissive of triglyceride synethesis by adipocytes.
C)It increases sensitivity of muscle and adipose to insulin,and inhibits gluconeogenesis in the liver.
D)It directly stimulates gluconeogenesis and lipolysis,and increases sensitivity of muscle and adipose to insulin.
E)It is permissive of gluconeogenesis and lipolysis,and reduces sensitivity of muscle and adipose to insulin.

Question 32

Which of the following statements regarding plasma cholesterol concentration and the development of atherosclerosis is correct?

A)It is preferable to have a high concentration of low-density lipoproteins (LDLs)in the plasma because LDLs operate to remove cholesterol from the peripheral tissues and carry it to the liver,which secretes it into the small intestine.
B)It is preferable to have a high concentration of high-density lipoproteins (HDLs)in the plasma because HDLs operate to remove cholesterol from the peripheral tissues and carry it to the liver,which secretes it into the small intestine.
C)It is preferable to have equal concentrations of LDL and HDL.
D)Neither LDL nor HDL are involved in cholesterol regulation.
E)Plasma cholesterol concentration has no relationship to atherosclerosis.

Question 33

Gluconeogenesis is stimulated by decreased levels of:

A)epinephrine.
B)insulin.
C)glucocorticoids.
D)growth hormone.
E)glucagon.

Question 34

Cholesterol is a:

A)precursor of steroid hormones.
B)component of DNA.
C)precursor of bile pigments.
D)carbohydrate.
E)vitamin.

Question 35

Which of the following contributes to a catabolic state?

A)increased plasma cortisol concentration
B)hypothyroidism
C)increased plasma androgen concentrations
D)increased plasma insulin concentration
E)decreased plasma glucagon concentration

Question 36

Which of the following acts to decrease blood glucose levels?

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

Question 37

Which is a symptom of untreated type 1 (insulin-dependent)diabetes mellitus?

A)low plasma ketones
B)increased blood volume
C)decreased respiration
D)hyperglycemia
E)increased plasma insulin

Question 38

In Addison's disease,the adrenal cortices degenerate.Which will result if a patient with this disease undergoes prolonged fasting?

A)hypoglycemia
B)hyperglycemia
C)excessive lipolysis
D)decreased insulin sensitivity
E)excessive liver gluconeogenesis

Question 39

Which event occurs during exercise but NOT during fasting?

A)increased breakdown of triglycerides
B)increased glycogenolysis
C)increased glucose uptake by muscle
D)increased fatty acid oxidation
E)increased cortisol secretion

Question 40

Which of the following is NOT a symptom that is associated with untreated type 1 diabetes mellitus (insulin-dependent diabetes mellitus)?

A)hypoglycemia
B)metabolic acidosis
C)dehydration
D)glucosuria (glucose in urine)
E) increased lipolysis

Question 41

A person's lowest metabolic rate

A) occurs during sleep.
B) occurs when they are younger.
C) occurs during exercise.
D) occurs after a meal.
E) occurs when body temperature increases.

Question 42

The subjective feeling of hunger is stimulated when:

A)plasma insulin concentration increases.
B)plasma ghrelin concentration decreases.
C)plasma leptin concentration decreases.
D)plasma glucose concentration increases.
E)body temperature increases.

Question 43

The thermoneutral zone is defined as:

A)the region in the central core of the body where temperature never changes.
B)the core body temperature at which no energy is expended to maintain homeostasis.
C)the environmental temperature range over which the changes in skin blood flow alone can regulate body temperature.
D)the region of the body halfway between the high-temperature core and the low-temperature skin.
E)the environmental temperature range in which shivering,changes in blood flow,and changes in thyroid hormone concentrations can maintain homeostasis of the body's core temperature.

Question 44

The primary integrator of body temperature control reflexes is the:

A)medullary cardiovascular center.
B)cerebral cortex.
C)thyroid gland.
D)hypothalamus.
E)adrenal medulla.

Question 45

If more calories are ingested in food than are expended by metabolism:

A)a person will gain weight.
B)a person will lose weight.
C)a person will stay the same weight because the excess energy is destroyed.
D) whether weight is gained or lost depends upon whether the calories are in the form of proteins,carbohydrates,or fat.

Question 46

Most of the triglycerides absorbed as chylomicrons are ultimately stored as fat in the adipose tissue.

Question 47

A person who is hypothyroid would be expected to:

A)have an increased basal metabolic rate.
B)have reduced tolerance for cold temperatures.
C)lose body weight.
D)be restless and irritable.
E)have symptoms similar to over-activation of the sympathetic nervous system.

Question 48

During the absorptive state,there is net synthesis of fat,glycogen,and protein,but this process is reversed during the postabsorptive state.

Question 49

Which of the following lists exclusively contains only variables that determine a person's basal metabolic rate?

A)gender,weight,age,and muscular activity
B)age,height,and recent ingestion of food
C)environmental temperature variations,body surface area,and emotional state
D)gender,age,body surface area,and circulating levels of thyroid hormone
E)environmental temperature,muscular activity,and emotional state

Question 50

Most of the energy used by the body during fasting is provided by gluconeogenesis.

Question 51

Acclimatization to a hot environment includes which of these physiological changes?

A)a decrease in the set point temperature regulated by the hypothalamus
B)decreased volume and increased salt concentration of sweat glands
C)decreased volume and salt concentration of sweat from the sweat glands
D)increased volume and salt concentration of sweat from the sweat glands
E)increased volume and decreased salt concentration of sweat from the sweat glands

Question 52

The source of the triglycerides used for synthesis of very low density lipoproteins in the liver is fatty acids and glycerol absorbed from the bloodstream by the liver.

Question 53

The principal means of increasing heat production in response to a cold environment is:

A)vasoconstriction of blood vessels in the skin.
B)wearing warm clothing.
C)shivering thermogenesis and increased voluntary activity.
D)vasodilation of blood vessels in skin.
E)increasing food intake to elevate the metabolic rate.

Question 54

Endogenous pyrogen:

A)is released by infection-fighting leukocytes and acts on muscle tissue.
B)is released by the hypothalamus and acts on infection-fighting leukocytes.
C)is released by infection-fighting leukocytes and has the same action as aspirin.
D)is released by infection-fighting leukocytes and acts on the temperature-integrating centers of the hypothalamus.
E)is released by the pyloric region of the stomach and raises the temperature of digestion.

Question 55

During normal metabolism of the human body,about 60% of the energy released from organic molecules:

A)is used to perform internal work.
B)is stored as ATP.
C)appears immediately as heat.
D)is stored as triglycerides.
E)is used to perform external work.

Question 56

Most of the glucose stored after a high-carbohydrate meal is stored in the form of glycogen.

Question 57

Ghrelin is secreted by _______________,and increases ________________ while decreasing _________________.

A)cells in the stomach; neuropeptide Y secretion; appetite
B)adipose tissue; growth hormone secretion; leptin secretion
C)muscle tissue; appetite; growh hormone secretion
D)cells in the stomach; appetite; fat breakdown
E)adipose tissue; appetite; fat breakdown

Question 58

Which factor,when increased,increases metabolic rate to the greatest extent?

A)skeletal muscle activity
B)mental activity
C)dietary caloric intake
D)environmental temperature
E)blood glucose levels

Question 59

During the absorptive state,the body makes use of stored nutrients for energy.

Question 60

Fatty acids released by lipolysis of triglycerides in adipose tissue travel in the plasma as VLDL.

Question 61

The effects of insulin in any given cell on membrane transport and on enzyme activity are mediated by the same receptor.

Question 62

The major energy sources for non-nervous tissue during the postabsorptive period are fatty acids and ketones.

Question 63

The calorigenic effect of thyroid hormones refers to their effect in increasing the rate at which the body synthesizes protein and fat.

Question 64

During exercise,glucose uptake by muscle cells is increased because of increased insulin secretion.

Question 65

The excretion of glucose in the urine of a diabetic patient is a result of the inability of the kidney tubules to reabsorb glucose in the absence of insulin.

Question 66

The chemoreceptors for the reflexes that stimulate sympathetic activity and epinephrine secretion in response to hypoglycemia are located in the carotid and aortic bodies.

Question 67

All other things being equal,a person who is hypothyroid will have a higher BMR than a person whose thyroid function is normal.

Question 68

When total-body energy balance is positive in an adult,energy is being stored as fat.

Question 69

The most important of the glucose-counterregulatory controls in normal circumstances is epinephrine.

Question 70

Cholesterol is metabolized to bile salts in the liver.

Question 71

In untreated Type 1 (insulin-dependent)diabetes mellitus,the liver converts fatty acids into ketones,which are released into the blood.

Question 72

Plasma cholesterol concentration is not homeostatically regulated,but instead depends solely on the intake of cholesterol in the diet.

Question 73

Pituitary growth hormone has effects on protein metabolism similar to those of insulin,but its effects on carbohydrate and lipid metabolism are similar to those of elevated cortisol.

Question 74

During stress,elevated levels of plasma cortisol stimulate the catabolism of muscle protein and the conversion of alpha-keto acids to glucose in the liver.

Question 75

Metabolic acidosis caused by excessive blood levels of ketones is one of the harmful consequences of untreated Type 1 (insulin-dependent)diabetes.

Question 76

One consequence of insulin deficiency is the decreased ability of the brain to take up blood glucose,a condition that can lead to brain dysfunction and death.

Question 77

Insulin has no effect on the carrier-mediated transport of glucose in the liver; therefore,insulin does not stimulate the uptake of glucose by that organ.

Question 78

Insulin inhibits the enzymes in the liver that catalyze reactions leading to gluconeogenesis.

Question 79

The metabolic events characteristic of the absorptive state can be attributed to the presence of large amounts of insulin in the blood,whereas the events of the postabsorptive state can be attributed largely to decreased insulin levels.

Question 80

Insulin is a satiety signal that suppresses appetite,whereas glucagon stimulates appetite.