chapter 6 and 7 test bank

Hormones are not typically considered to be cytokines because hormones are ________ like cytokines. A) synthesized in advance and stored, not B) not peptides C) not effective in small amounts D) secreted into the blood, not E) secreted by cells, not

A

Synergism occurs when A) one hormone triggers the secretion of a second hormone. B) one hormone inhibits the release of a second hormone. C) hormones working together produce a larger effect than predicted. D) hormones working together produce a smaller effect than predicted. E) a hormone can exert its full effects only in the presence of another hormone.

C

In a simple endocrine reflex, the endocrine cell is the A) sensor only. B) integrating center only. C) target. D) sensor and integrating center. E) integrating center and target.

D

The nervous system has a role in preserving the "fitness" of the ________.

Internal Environment

________ is a process by which an extracellular signal molecule, called the ________, activates a membrane receptor that in turn alters intracellular molecules, called the ________, to create a response.

Signal transduction, first messenger, second messenger

One intracellular calcium-binding protein is A) calmodulin. B) calcitonin. C) calcitriol. D) IP3. E) nitric oxide.

a

The majority of hormones in the body are A) peptide hormones. B) steroid hormones. C) amino acid-derived hormones. D) neurohormones. E) All of the hormones are present in equal amounts in the body.

a

The pituitary hormone that controls hormone synthesis and release from the thyroid gland is A) TSH. B) ACTH. C) FSH. D) LH. E) STH.

a

When stimulated by a particular hormone, there is a marked increase in the activity of G proteins in the membrane. The hormone is probably A) a steroid. B) a peptide. C) testosterone. D) estrogen. E) aldosterone.

a

the minimum stimulus to trigger a response A. threshold B. effector C. integrating center D. setpoint E. sensory receptor

a

adrenal cortex hormone

aldosterone

derivatives of tyrosine

amino acid-derived hormone

Two hormones that have opposing effects are called ________.

antagonists

true endocrine gland of epithelial origin

anterior pituitary

If the signal molecule acts on the cell that secreted it, the chemical is called a(n) ________.

autocrine

Down-regulation may allow a target cell to A) only increase its number of receptors for a ligand. B) only decrease its number of receptors for a ligand. C) only increase its binding affinity for a ligand. D) decrease the receptors' binding affinity and increase its number of receptors.

b

Steroid hormones are synthesized in the ________ of the cell. A) rough endoplasmic reticulum B) smooth endoplasmic reticulum C) Golgi apparatus D) mitochondria E) nucleus

b

The most significant difference between a paracrine and an autocrine is A) the cell that releases it. B) the cell that responds to it. C) the method of transport. D) the route of transport. E) There are no differences—they are the same.

b

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

b

When a catecholamine or peptide hormone binds to receptors on the surface of a cell, A) the cell membrane becomes less permeable. B) a second messenger appears in the cytoplasm. C) the cell becomes inactive. D) the hormone is transported to the nucleus where it alters the activity of DNA. E) None of the answers are correct.

b

When adenylyl cyclase is activated, A) calcium ions are released from intracellular stores. B) cAMP is formed. C) cAMP is broken down. D) protein kinases are metabolized. E) steroids are produced.

b

the organ or gland that performs the change A. threshold B. effector C. integrating center D. setpoint E. sensory receptor

b

After a hormone has exerted its effects, it typically A) continues to act until an opposing hormone is secreted. B) spontaneously degrades. C) is inactivated or removed from the blood. D) is absorbed by its target cell. E) is absorbed by the gland that secreted it.

c

An integrating center A) is the disturbance or change that sets the pathway in motion. B) is an electrical and/or chemical signal that travels to the effector. C) evaluates incoming signals and compares it with the setpoint. D) is the minimum stimulus that must be achieved to set the reflect response in motion.

c

receives information about the regulated variable and initiates a response A. threshold B. effector C. integrating center D. setpoint E. sensory receptor

c

thyroid hormone

calcitonin

A gap junction forms when opposing membrane-spanning proteins called ________ on two adjacent cells unite, creating a protein channel that is capable of opening and closing.

connexins

Cyclic AMP activates A) a G protein. B) adenylyl cyclase. C) protein hormones. D) protein kinase A .E) hormone receptors.

d

Each of the following hormones is an amino acid derivative EXCEPT one. Identify the exception. A) epinephrine B) norepinephrine C) thyroid hormone D) thyroid-stimulating hormone E) melatonin

d

Each of the following statements concerning peptide hormones is true EXCEPT one. Identify the exception. A) Peptide hormones are first synthesized as prohormones. B) Prohormones can be activated before their release via post-translational modification. C) Peptide hormones remain in circulation for relatively short periods of time. D) Peptide hormones in the bloodstream are always bound to carrier proteins. E) Peptide hormones interact with receptors on the surface of their target cells.

d

The binding of lipophilic messengers, such as steroid hormones, to their receptors triggers A) adenylyl cyclase activation. B) cyclic nucleotide formation. C) G protein inhibition .D) gene transcription. E) protein kinase activation.

d

The intracellular effector in chemical signaling is often A) a hormone. B) a membrane receptor molecule. C) ATP. D) a protein kinase. E) cholesterol.

d

The link between a first messenger and a second messenger in a cell that responds to peptide hormones is usually A) cAMP. B) cGMP. C) adenylyl cyclase. D) a G protein. E) calcium.

d

he most complex endocrine responses involve the A) thyroid gland. B) pancreas. C) adrenal glands. D) hypothalamus. E) thymus.

d

inositol triphosphate A) is a water-insoluble messenger molecule. B) binds to the calcium channel of the endoplasmic recticulum. C) is involved in the release of calcium into the cytosol. D) is a second messenger that is involved in the release of calcium into the cytosol E) uses all of the mechanisms.

d

the desired target value for a parameter A. threshold B. effector C. integrating center D. setpoint E. sensory receptor

d

_________ can be caused by alterations in receptors or by problems with G protein or second messenger pathways.

diseases

18) Which of the following are considered differences between endocrine and neural control systems? A) specificity B) nature of the signal C) speed D) duration of action E) All of the answers are correct.

e

Diacylglycerol is produced from A) cyclic AMP. B) phospholipase C. C) a G protein. D) protein kinase A. E) phosphatidylinositol bisphosphate.

e

Receptor molecules are located A) only in the outer cell membrane. B) only in the cytosol. C) only in the nucleus. D) only on the cell surface. E) in all of these places.

e

Second messenger molecules directly A) change the regulation of ion channels. B) increase intracellular calcium concentration. C) change enzyme activity. D) change regulation of gene expression. E) All of the answers are correct.

e

The pituitary hormone that stimulates cell growth and metabolism in many tissues is A) ACTH. B) MSH. C) prolactin. D) insulin. E) somatotropin.

e

Which of the following is NOT a method of hormone action? A) control of enzymatic reaction rates B) control of ion or molecule transport across cell membranes C) control of electrical signaling pathways D) control of gene expression and protein synthesis E) All are methods of hormone action.

e

continuously monitors its environment for a specific variable A. threshold B. effector C. integrating center D. setpoint E. sensory receptor

e

Lipid signal molecules that act in a paracrine fashion and combine with G-protein coupled receptors include ________ and ________.

eicosanoids, sphingolipids

The study of hormones is known as the field of ________.

endocrinology

adrenal medulla hormone

epinephrine

The ________ link membrane receptors to either ion channels or to membrane enzymes located on the cytoplasmic face of the membrane.

g-proteins

site of vasopressin synthesis

hypothalamus

pancreas hormone

insulin

pineal gland hormone

melatonin

All molecules secreted by nerve cells (neuromodulators, neurotransmitters, and neurohormones) are known as ________.

neurocrines

Chemical signals released into the blood by neurons are called ________.

neurohormones

A few gases are known to act as signal molecules, including ________, ________, and ________.

nitric oxide, carbon monoxide, hydrogen sulfide

A chemical that is secreted by a cell to act on cells in its immediate vicinity is called a(n) _______

paracrine

lipophobic molecule that interacts with receptors on cell surface

peptide hormone

The term that describes the need for one hormone to be present for a second hormone to produce a full effect is called ________.

permissive

A circulatory route that has two sets of capillaries is known as a ________.

portal system

storage and release site for oxytocin

posterior pituitary

________ pathologies arise in the last endocrine gland in a reflex.

primary

anterior pituitary hormone

prolactin

Many second messenger systems activate ________, enzymes that transfer a phosphate group from ATP to a protein. The phosphorylation of proteins sets off a series of intracellular events that lead to the ultimate cellular response.

protein kinases

An intracellular signal molecule that translates a signal from a neurotransmitter or hormone into an intracellular response is called a

second messenger

A ________ is a problem with one of the tissues producing trophic hormones.

secondary pathology

cannot be stored in secretory vesicles

steroid hormone

The term for two hormones that have additive effects is ________.

synergists

Peripheral cells sensitive to the presence of hormones are called ________.

targets

The term for any hormone that controls the secretion of another hormone is a ________.

trophic hormone