Chapter 9 (Homeostasis)

Question 1

homeostasis

Answer 1

The active process of maintaining a particular physiological parameter relatively constant.

Question 2

motivation

Answer 2

The psychological process that induces or sustains a particular behavior

Question 3

endotherm

Answer 3

An animal whose body temperature is regulated chiefly by internal metabolic processes. Examples include mammals and birds.

Question 4

ectotherm

Answer 4

An animal whose body temperature is regulated by, and whose heat comes mainly from, the environment.

Question 5

negative feedback

Answer 5

The property by which some of the output of a system feeds back to reduce the effect of input signals.

Question 6

set point

Answer 6

The point of reference in a feedback system. An example is the temperature at which a thermostat is set.

Question 7

set zone

Answer 7

The range of a variable that a feedback system tries to maintain.

Question 8

intracellular compartment

Answer 8

The fluid space of the body that is contained within cells.

Question 9

extracellular compartment

Answer 9

The fluid space of the body that exists outside the cells.

Question 10

diffusion

Answer 10

The spontaneous spread of solute molecules through a solvent until a uniform solute concentration is achieved.

Question 11

osmosis

Answer 11

The passive movement of a solvent, usually water, through a semipermeable membrane until a uniform concentration of solute (often salt) is achieved on both sides of the membrane.

Question 12

osmotic pressure

Answer 12

The tendency of a solvent to move across a membrane in order to equalize the concentration of solute on both sides of the membrane.

Question 13

hypovolemic thirst

Answer 13

A desire to ingest fluids that is stimulated by a reduction in volume of the extracellular fluid.

Question 14

osmotic thirst

Answer 14

A desire to ingest fluids that is stimulated by loss of water from the extracellular compartment.

Question 15

baroreceptor

Answer 15

A pressure receptor in the heart or a major artery that detects a change in blood pressure.

Question 16

atrial natriuretic peptide (ANP)

Answer 16

A hormone, secreted by the heart, that normally reduces blood pressure, inhibits drinking, and promotes the excretion of water and salt at the kidneys.

Question 17

vasopresin or arginine vasopresin

Answer 17

Also called antidiuretic hormone (ADH). A peptide hormone from the posterior pituitary that promotes water conservation and increases blood pressure.

Question 18

angiotensin II

Answer 18

A hormone that is produced in the blood by the action of renin and that may play a role in the control of thirst.

Question 19

circumventricular organ

Answer 19

Any of multiple distinct sites that lie in the wall of a cerebral ventricle and monitor the composition of the CSF.

Question 20

aldosterone

Answer 20

A mineralocorticoid hormone, secreted by the adrenal cortex, that promotes the conservation of sodium by the kidneys.

Question 21

nutrient

Answer 21

A chemical that is needed for growth, maintenance, and repair of the body but is not used as a source of energy.

Question 22

glucose

Answer 22

An important sugar molecule used by the body and brain for energy.

Question 23

glycogen

Answer 23

A complex carbohydrate made by the combining of glucose molecules for a short-term store of energy.

Question 24

insulin

Answer 24

A pancreatic hormone that lowers blood glucose, promotes energy storage, and facilitates glucose utilization by cells.

Question 25

glucagon

Answer 25

A pancreatic hormone that converts glycogen to glucose, and thus increases blood glucose.

Question 26

lipid

Answer 26

A large molecule (commonly called a fat) that consists of fatty acids at glycerol that are insoluble in water.

Question 27

adipose tissue

Answer 27

Commonly called fat tissue. Tissue made up of fat cells.

Question 28

ketone

Answer 28

A compound, liberated by the breakdown of body fats and proteins, that is a metabolic fuel source.

Question 29

basal metabolism

Answer 29

The consumption of energy to fuel processes such as heat production, maintenance of membrane potentials, and all the other basic life-sustaining functions of the body.

Question 30

diabetes mellitus

Answer 30

A condition, characterized by excessive glucose in the blood and urine and by reduced glucose utilization by body cells, that is caused by the failure of insulin to induce glucose absorption.

Question 31

glucodetector

Answer 31

A specialized type of liver cell that detects and informs the nervous system about levels of circulating glucose.

Question 32

ventromedial hypothalamus (VMH)

Answer 32

A hypothalamic region involved in eating and sexual behaviors.

Question 33

lateral hypothalamus (LH)

Answer 33

A hypothalamic region involved in the control of appetite and other functions.

Question 34

arcuate nucleus

Answer 34

An arc-shaped hypothalamic nucleus implicated in appetite control.

Question 35

leptin

Answer 35

A peptide hormone released by fat cells.

Question 36

ghrelin

Answer 36

A peptide hormone produced and released by the gut.

Question 37

PPY(3-36)

Answer 37

A peptide hormone, secreted by the intestines, that probably acts on hypothalamic appetite control mechanisms to suppress appetite.

Question 38

NPY neuron

Answer 38

A neuron, involved in the hypothalamic appetite control system, that produces both neuropeptide Y and agouti-related peptide.

Question 39

POMC neuron

Answer 39

A neuron, involved in the hypothalamic appetite control system, that produces both pro-opiomelanocortin and cocaine- and amphetamine-related transcript.

Question 40

orexin

Answer 40

Also called hypocretin. A neuropeptide produced in the hypothalamus that is involved in switching between sleep states, in narcolepsy, and in the control of appetite.

Question 41

nucleus of the solitary tract (NST)

Answer 41

A complicated brainstem nucleus that receives visceral and taste information via several cranial nerves.

Question 42

cholecystokinin (CCK)

Answer 42

A peptide hormone that is released by the gut after ingestion of food that is high in protein and/or fat.

Question 43

endocannabinoid

Answer 43

An endogenous ligand of cannabinoid receptors; thus, a marijuana analog that is produced in the brain.

Question 44

liposuction

Answer 44

The surgical removal of fat.

Question 45

bariatric

Answer 45

Having to do with obesity.

Question 46

anorexia nervosa

Answer 46

A syndrome in which individuals severely deprive themselves of food.

Question 47

bulimia nervosa

Answer 47

A syndrome in which individuals periodically gorge themselves, usually with “junk food,” and then either vomit or take laxatives to avoid weight gain.