Biopsych Prelim 3

Front 1

set point

Back 1

a desired value

-negative feedback works to get body back to the set point when there are deviations from homeostasis

Front 2

set zone

Back 2

for most systems, there is really a set zone that the system can be in

without some tolerance, the system would be going on and off very frequently.

Front 3

obligatory losses

Back 3

urination, heating the body, etc.

we have to always make up for these

Front 4

ectotherms

Back 4

regulate their body temperature through behavioral means

ex_ moving to favoralbe sites or chaning their exposure to external sources of heat.

Front 5

endotherms

Back 5

primarily regulate body temperature by making internal adjustments

regulate their body temp chiefly by internal metabolic processes


-generate heat through metabolism.

Front 6

advantages and disadvantages of endothermy

Back 6

advantage--greater independence from environmental conditions

advantage---in order to fuel chemical reactions in the body through which they generate heat, endotherms evolved a greater capacity for oxygen utilization.. allows us to sustain high levels of muscle activity over longer periods of time
disadvantage--requires a lot of energy.

Front 7

brown fat

Back 7

found around vital organs in the trunk

full of mitochondria.

break down molecules and produce heat.

under cold conditions, the sympathetic nervous system stimulates the metablolism within brown fat cells, producing heat.

Front 8

behavioral thermoregulatory responses of ectotherms and endotherms

Back 8

1) changing exposure of the body surface
ex) huddling

2) changing external insulation
ex) using clothing or nests

3) selecting a surrounding that is less thermally stressful
ex) going to the shade

Front 9

torpor

Back 9

saves a lot of energy for the animal.

Front 10

brain regulation of body temperature

Back 10

body temperature is regulated in the hypothalamus.

ex) small lesions in dog hypothalamus increased body temperature.


lateral hypothalamus
controls behavioral temperature regulation

POA
-controls autonomic responses to temperature.

-parallel circuits for two ways of regulating the same variable.

Front 11

extracellular compartment

Back 11

water that's outside our cells

broken up into interstitial fluid (fluid between cells) and blood plasma

Front 12

aquaporins

Back 12

proteins that make up specialized water channels that allow water to move back and forth between cells nad in and out of cells.

Front 13

osmolality

Back 13

the concentration of solute in a solution

Front 14

isotonic solution

Back 14

has same salt concentration as mammalian fluids have

Front 15

hpyertonic

Back 15

more salt than mammalian fluids have

Front 16

hypotonic

Back 16

less salt than mammalian fluids have.

Front 17

hypovolemic thirst

Back 17

low extracellular volumes of water

triggered by the loss of blood or other body fluids

extracellular fluid is depleted w/o changes in solute concentration.

no osmotic pressure to push water from one compartment to another

causes release of vasopressin (ADH) to reduce urination and constrict blood vessels.

renin and angiotensin are also released to conserve water.

Front 18

osmotic thirst

Back 18

high extracellular solut concentration.

total volume of water is constant, but a sudden increas in the amount of solute in the extracellular comparrtment exerts osmotic pressure that pulls water out of the intracellular compartment.

how thirst is most commonly produced.

obligatory water losses where more water is lost than salt messes up the concentrations of fluids.

some hypothalamic cells might be osmosensory neurosn--cells that respond to changes in osmotic pressure

Front 19

diabetes insipidus

Back 19

the production of vasopressin ceases, and the kidneys retain less water.

they send more urine to the bladder, and that urine is very pail and dilute.

chronic thirst.

Front 20

aldosterone

Back 20

is crucial to sodium conservation.

aids water retention by acting on the kidneys, inducing them to conserve sodium

Front 21

glycogon

Back 21

form of glucose used for storage

Front 22

sequential mechanisms that stimulate insulin release

Back 22

1)stimul from food evokes a conditioned rlease of insluin in anticipation of glucoes arrival in the blood.

2)

Front 23

diabetes mellitus

Back 23

real diabetes

type one
-the pancreas stops producing insulin

type two
-insulin insensitivity

Front 24

Ventromedial hypothalamus lesions

Back 24

-produces obesity

Front 25

lateral hypothalamus lesions

Back 25

anorexia

Front 26

leptin

Back 26

secreted by fat cells

report how fat the body is

Front 27

gherlin

Back 27

powerful appetite stimulant

one mechanism for obesity might be a gherlin system that is unresponsive to feeding

Front 28

PYY

Back 28

appetite suppressing

increases in concentration after eating

Front 29

CART and POMC

Back 29

inhibit appetite and increase metabolism

both project to the lateral hypothalamus

Front 30

NPY/AgRP system

Back 30

appetite stimulating