Ch 13 - Homeostasis

Question 1

Homeostasis

Answer 1

Maintaining physiological traits w/in a specific range (set point or set range)

Question 2

Motivation

Answer 2

A drive state that prompts homeostatic behaviors

Question 3

Obligatory losses

Answer 3

Unavoidable loss of a regulated variable such as energy, water, or temp, as a consequence of life processes.

Question 4

POA body temp regulation

Answer 4

Physiological responses (ex. Shivering)

Question 5

Lateral hypothalamus (LH) body temp

Answer 5

Behavioral responses. Ex change exposure of skin.

Question 6

Receptors that detect body temp

Answer 6

In skin, body core, hypothalamus.

Report to spinal cord, brainstem, and hypothalamus.

Question 7

Intracellular compartment

Answer 7

The fluid space of the body that is contained within cells

Question 8

Exrracellelar compartment

Answer 8

The fluid space of the body that exists outside the cells

Question 9

Aquaporins

Answer 9

Channels spanning cell membranes that are specialized for conducting water molecules in or out of cell

Question 10

Osmotic pressure

Answer 10

The tendency of a solvent to move through a membrane in order to equalize the concentration of solute.

Question 11

Osmolality

Answer 11

Number of solute particles per unit volume of solvent

Question 12

Hypovolemic thirst

Answer 12

Thirst based on reduced volume of extracellular fluid. Lose equal amounts of salt and water

Question 13

Osmotic thirst

Answer 13

Thirst stimulated by loss of water from the extracellular compartment. More water lost than salt. Alters solute concentration between intra and extra cellular space

Question 14

Atrial natriuretic peptide (ANP)

Answer 14

Released from heart that normally reduces bp, inhibits drinking and promotes excretion of water and salt at the kidneys. Decreases w hypovolemic thirst

Question 15

Vasopressin aka ADH

Answer 15

Secreted by posterior pituitary. Tells kidney to conserve water, constricts blood vessels to raise bp

Question 16

Renin

Answer 16

Enzyme from kidney, cleaves angiotensin to angiotensin2.

Question 17

Angiotensin2

Answer 17

Increases aldosterone release from adrenal gland, increases vasopressin, tells hypothalamus to increase drinking behavior, blood vessels constrict

Question 18

Osmosensory neurons

Answer 18

I’m hypothalamus, respond to changes in osmolality. Detect mechanical change bc they are stretchy.

Question 19

Alcohol effects on fluid regulation

Answer 19

Inhibits ADH so have osmotic loss of water

Next day pituitary releases ADH but still thirsty, feel bloated bc of ADH

Question 20

Anticipation of system to drinking

Answer 20

Amount of water in mouth, blood volume, osmolality

Question 21

VMH

Answer 21

Satiety center (paraventricular nucleus)

Question 22

LH

Answer 22

Hunger center. Increase appetite. Motivation for seeking food-DA pathway.

Question 23

Arcuate nucleus

Answer 23

Collects info from many sources on hunger and food. Signals from insulin, leptin, ghrelin, PYY3-36

Question 24

Insulin

Answer 24

Produced in pancreas- reduced glucose in blood

Question 25

Leptin

Answer 25

Produced in fat cells. Tells body to stop storing fat.

Question 26

Ghrelin

Answer 26

Released by stomach. Appetite suppressant. Sends signal when stomach is full

Question 27

PYY3-36

Answer 27

Produced in intestines. Satiety signal.