MCQ Hormonal Regulation Flashcards Preview

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Flashcards in MCQ Hormonal Regulation Deck (18)
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1
Q

One distinction between peptide and steroid hormones is that peptide hormones:
A) act through nonspecific receptors, whereas steroid hormones act through specific receptors.
B) are generally water-insoluble, whereas steroid hormones are water soluble.
C) are more stable than steroid hormones.
D) bind to cell surface receptors, whereas steroid hormones bind to nuclear receptors.
E) bind to their receptors with high affinity, whereas steroid hormones bind with low affinity

A

D) bind to cell surface receptors, whereas steroid hormones bind to nuclear receptors.

2
Q
Insulin is an example of a(n) \_\_\_\_\_\_\_\_\_\_\_\_ hormone.
A) catecholamine B) eicosanoid
C) paracrine
D) peptide
E) steroid
A

D) peptide

3
Q
The maturation of insulin from its precursor (preproinsulin) involves:
A) acetylation.
B) oxidation.
C) phosphorylation. D) proteolysis.
E) reduction.
A

D) proteolysis.

4
Q
Epinephrine is an example of a(n) \_\_\_\_\_\_\_\_\_\_\_\_ hormone.
A) catecholamine B) eicosanoid
C) paracrine
D) peptide
E) steroid
A

A) catecholamine

5
Q
An example of an eicosanoid hormone is:
A) epinephrine.
B) retinoic acid.
C) testosterone.
D) thromboxane.
E) thyroxine.
A

D) thromboxane.

6
Q
The tropic hormones (such as thyrotropin, somatotropin, and luteinizing hormone) are produced and released by the:
A) anterior pituitary.
B) hypothalamus.
C) ovaries.
D) pancreas.
E) posterior pituitary.
A

A) anterior pituitary.

7
Q

Which of the following statements about metabolism in the mammalian liver is false?
A) Most plasma lipoproteins are synthesized in the liver.
B) The enzymatic complement of liver tissue changes in response to changes in the diet.
C) The liver synthesizes most of the urea produced in the body.
D) The presence of glucose 6-phosphatase makes liver uniquely able to release glucose into the
bloodstream.
E) Under certain conditions, most of the functions of the liver can be performed by other organs.

A

E) Under certain conditions, most of the functions of the liver can be performed by other organs.

8
Q

Glucokinase:
A) actsintheconversionofliverglycogentoglucose1-phosphate.
B) converts fructose-6-phosphate to glucose-6-phosphate
C) converts glucose 6-phosphate to fructose 6-phosphate.
D) isahexokinaseisozymefoundinliverhepatocytes.
E) is found in all mammalian tissues.

A

D) isahexokinaseisozymefoundinliverhepatocytes

9
Q

In skeletal muscle:
A) amino acids are an essential fuel.
B) at rest, fatty acids are the preferred fuel.
C) large quantities of triacylglycerol are stored as fuel.
D) phosphocreatine can substitute for ATP as the direct source of energy for muscle contraction.
E) stored muscle glycogen can be converted to glucose and released to replenish blood glucose.

A

at rest, fatty acids are the preferred fuel.

10
Q

Which one of the following statements is true?
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

A) The brain prefers glucose as an energy source, but can use ketone bodies.

11
Q

When blood glucose is abnormally high, the pancreas releases:
A) epinephrine. B) glucagon. C) glucose.
D) insulin.
E) trypsin.

A

D) insulin.

12
Q

When blood glucose is abnormally low, the pancreas releases:
A) epinephrine. B) glucagon. C) glucose.
D) insulin.
E) trypsin.

A

B) glucagon.

13
Q

An elevated insulin level in the blood:
A) inhibits glucose uptake by the liver.
B) inhibits glycogen synthesis in the liver and muscle.
C) results from a below-normal blood glucose level.
D) stimulates glycogen breakdown in liver.
E) stimulates synthesis of fatty acids and triacylglycerols in the liver.

A

E) stimulates synthesis of fatty acids and triacylglycerols in the liver.

14
Q
The largest energy store in a well-nourished human is:
A) ATP in all tissues.
B) blood glucose.
C) liver glycogen.
D) muscle glycogen.
E) triacylglycerols in adipose tissue.
A

E) triacylglycerols in adipose tissue.

15
Q

Elevated epinephrine levels do not normally stimulate:
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

D) glycogen synthesis in liver.

16
Q

Epinephrine triggers an increased rate of glycolysis in muscle by:
A) activationofhexokinase.
B) activation of phosphofructokinase-1.
C) conversion of glycogen phosphorylase a to glycogen phosphorylase b.
D) inhibitionoftheCoriCycle
E) the Pasteur effect.

A

B) activation of phosphofructokinase-1.

17
Q
Long-term maintenance of body weight is regulated by the hormone:
A) adiposin.
B) hypothalmin. C) leptin.
D) obesin.
E) testosterone.
A

C) leptin.

18
Q

The peptide hormone adiponectin, produced in adipose tissue, circulates in the blood and:
A) enhancesfattyacidsynthesisinlivercells.
B) increases the rate of β-oxidation of fatty acids in muscle cells.
C) inhibits glucose uptake and catabolism in muscle and liver cells.
D) reducesthetransportoffattyacidsintomusclecells.
E) stimulates gluconeogenesis in liver cells.

A

B) increases the rate of β-oxidation of fatty acids in muscle cells.