Ch. 10

Hypothalamic signals reach the anterior pituitary through the A) infundibulum. B) hypophyseal portal system. C) hypothalamic axons. D) hypophysis. E) thymus.

B

Steroid hormones A) are proteins. B) are structurally similar to cholesterol. C) are the largest class of hormones. D) include pancreatic hormones. E) are secreted by the hypothalamus and pituitary gland.

B

The hormone oxytocin A) reduces uterine contractions. B) is involved in the milk "letdown" reflex. C) regulates blood pressure. D) governs the ovarian cycle. E) stimulates melanocytes in the skin.

B

Diabetes insipidus can be caused by A) decreased levels of insulin. B) decreased numbers of insulin receptors. C) failure of the kidneys to respond to ADH. D) increased numbers of ADH receptors. E) increased levels of ADH.

C

Excessive urine production, which is a characteristic symptom of all forms of diabetes, is known as A) polyphagia. B) polydipsia. C) polyuria. D) polymyositis. E) diabetes mellitus.

C

Hormone concentration levels are most commonly controlled by A) positive feedback. B) the quantity of circulating hormone. C) negative feedback. D) cellular demands. E) body temperature.

C

Peripheral structures sensitive to the presence of hormones are called A) exocrine cells. B) first messengers. C) target cells. D) second messengers. E) G-proteins.

C

The posterior pituitary gland stores A) follicle-stimulating hormone (FSH). B) thyroid-stimulating hormone (TSH). C) adrenocorticotropic hormone (ACTH). D) oxytocin (OT). E) melanocyte-stimulating hormone (MSH).

D

Hypothalamic hormones that stimulate the synthesis and secretion of one or more hormones in the anterior lobe are called A) permissive hormones. B) synergistic hormones. C) regulating hormones. D) stimulating hormones. E) releasing hormones.

E

In the simplest case, endocrine activity may be controlled by changes in the extracellular fluid composition called ________ stimuli. A) hormonal B) cellular C) neural D) membrane E) humoral

E

Which of the following is released by the posterior pituitary? A) adrenocorticotropic hormone (ACTH) B) thyroid-stimulating hormone (TSH) C) growth hormone (GH) D) antidiuretic hormone (ADH) E) melanocyte-stimulating hormone (MSH)

D

The hypothalamus transports hormones to the posterior pituitary by way of A) neural axons, directly. B) direct mechanical control. C) releasing and inhibiting hormones. D) altering ion concentrations in the anterior pituitary. E) gap junctions.

A

The nervous system A) is ideal for crisis management. B) communicates mainly by the release of hormones. C) has effects that are very long-lived. D) is regulated mainly by positive feedback. E) does not rely on the binding of receptors to target cells.

A

Which statement regarding growth hormone (GH) is true? A) GH stimulates the breakdown of stored fats and the release of fatty acids into the blood. B) Liver cells respond to GH by releasing prostaglandins. C) Skeletal muscle cells and chondrocytes are extremely insensitive to GH. D) GH production is regulated by releasing and inhibiting hormones from the thyroid. E) In epithelial tissues, GH inhibits stem cell division.

A

Generally, the actions of hormones A) tend to be less widespread than actions of the nervous system. B) can produce complex changes in physical structure and physiological changes. C) are faster to react than the nervous system. D) are shorter-lasting than the actions of the nervous system. E) do not affect homeostasis.

B

Hormones from the ________, which travel in the hypophyseal portal vessels, alter the activity of the anterior pituitary. A) brain stem B) hypothalamus C) cerebellum D) thyroid E) thalamus

B

This condition develops when the posterior pituitary no longer releases adequate amounts of ADH. A) diabetes mellitus B) diabetes insipidus C) pituitary dwarfism D) exophthalmos E) gigantism

B

Two hormones referred to as gonadotropins are A) GH and TSH. B) FSH and LH. C) ADH and ACTH. D) PRL and OT. E) ADH and OT.

B

Which of the following hormones is an amino acid derivative? A) ADH B) melatonin C) oxytocin D) growth hormone E) prolactin

B

Which of the following primarily targets the gonads (ovaries and testes)? A) growth hormone B) follicle-stimulating hormone C) prolactin D) insulin E) thyroxine

B

Target cells of hypothalamic releasing and inhibiting hormones are located in the A) thymus gland. B) suprarenal gland. C) anterior pituitary. D) posterior pituitary. E) testes.

C

The hormone leptin is secreted by (the) A) pancreas. B) kidneys. C) adipose tissue. D) hypothalamus. E) anterior pituitary.

C

When a protein or peptide hormone binds to receptors on the surface of a cell, A) the hormone receptor complex moves into the cytoplasm. B) the plasma membrane becomes depolarized. C) a second messenger appears in the cytoplasm. D) the cell becomes inactive. E) the hormone is transported to the nucleus, where it alters the activity of the DNA.

C

Where are the hormones secreted by the posterior pituitary made? A) thyroid B) anterior pituitary C) hypothalamus D) posterior pituitary E) suprarenal gland

C

Cyclic AMP often causes activation of A) calcium ion channels. B) myosin kinase. C) phosphodiesterase. D) kinase enzymes. E) steroids.

D

Steroid hormones A) bind to receptors on the surface of the cell. B) function by way of a second messenger system. C) cannot diffuse through the plasma membrane. D) bind to intracellular receptors. E) function by activating cAMP.

D

The highest level of endocrine control is provided by the A) thyroid gland. B) pancreas. C) suprarenal glands. D) hypothalamus. E) thymus.

D

All hormones are A) steroids. B) cholesterol based. C) proteins. D) inorganic compounds. E) chemical messengers.

E

Another name for antidiuretic hormone is A) cortisol. B) parathyroid hormone. C) thymosin. D) growth hormone. E) vasopressin.

E

The endocrine system A) releases neurotransmitters into the bloodstream for distribution throughout the body. B) is regulated mainly by positive feedback. C) produces effects that last for seconds or minutes. D) is not involved in homeostasis. E) relies on the release of chemicals that bind to target cells.

E

The pituitary hormone that stimulates the breakdown of stored fats and the release of fatty acids into the bloods is A) TSH. B) ACTH. C) MSH. D) LH. E) GH.

E

Which statement is true regarding steroid hormones? A) They are carbohydrates. B) They cannot diffuse through the plasma membrane. C) They do not bind to receptors in the cytoplasm or nucleus. D) They cannot change the nature or number of enzymes in the cytoplasm. E) They can alter the rate of mRNA transcription.

E

Which of the following hormones bind to membrane receptors and activate G-proteins? A) peptide hormones B) steroid hormones C) estrogen D) thyroid hormones E) cortisol

A

Which of the following hormones enter a cell by diffusion? A) steroid hormones B) epinephrine and norepinephrine C) amino acid derivatives D) peptide hormones E) oxytocin

A

Which statement is true about the pituitary? A) The anterior pituitary controls the posterior pituitary. B) The alternate name for the pituitary is the infundibulum. C) The hypothalamus communicates with the anterior pituitary only. D) The pituitary hormones all work by activating G proteins and triggering cAMP within cells. E) The pituitary glands, both anterior and posterior, control every other endocrine gland.

D

The effect of prolactin closely interacts with the hormone A) oxytocin. B) renin. C) ADH. D) melatonin. E) calcitonin.

A

The pituitary hormone that controls the release of glucocorticoids is A) TSH. B) ACTH. C) FSH. D) LH. E) MSH.

B

The pituitary hormone that promotes testosterone release in males and ovulation in females is A) TSH. B) ACTH. C) FSH. D) LH. E) GH.

D

Peptide hormones are A) composed of chains of amino acids. B) released by the reproductive organs. C) derived from arachidonic acid. D) lipids. E) chemically related to cholesterol.

A

Which of the following hormones is secreted by the human pituitary during fetal development in very young children and in pregnant women, but is not usually found in adults? A) MSH B) TSH C) ACTH D) LH E) PRL

A

An important second messenger in hormonal action is A) cAMP. B) calcitriol. C) insulin. D) calcium. E) glucagon.

A