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Flashcards in hypothal 2 Deck (20):
1

Homeostasis

the ANS provides crucial input to the integrated responses capable of maintaining body temperature, body weight, and water balance.

2

Emotional responses:

the ANS is responsible for control on unconscious physical responses to stress/emotion such as blushing, dry mouth, sweating, GI reactions and fainting.

3

Somatic response: water balance

1. Thirst (motivated behavior)
--Increased drinking
--Decreased drinking
2. Achieved by swallowing fluids

4

endocrine response: Water balance:

Increase or decrease release of vasopressin from posterior pituitary

5

autonomic response: Body weight:

1. Hunger: reflects changes in
GI motility
2. Increase or
decrease digestion processes (Epi)

6

somatic response: body weight

1. Increase or decrease food acquisition (motivated behavior)
2. Chewing
3. Swallowing

7

endocrine response: body weight

1. Insulin/glucagon
2. Epinephrine

8

Autonomic response: heat production

Non-shivering thermogenesis

9

Non-shivering thermogenesis

1. brown fat (mitochondira high)
2. occurs via activation of thermogenin
3. when thermogenin is opened, allows H+ to leak across the membrane, generating heat without generating ATP
4. uncoupling of oxidative phosphorylation

10

Increase NE on brown fat cells by symp. fibers significantly ____

increases its catabolic activity

11

thermogenin

1. uncoupling protein 1
2. H+ ion channel of inner mitochondrial membrane

12

when thermogenin is open,

1. allows H+ to leak across the membrane, generating heat without generating ATP
2. uncouples oxidative phosphorylation

13

Somatic response of heat production

Motor response:
1. Increase exercise
Increases heat production 7 fold
2. Increase shivering
Increases heat production 2 fold

14

Endocrine response to heat production

Thyroxin

15

Thyroxin is regulated by

HT control of anterior pituitary

Increase thyroxin = increase basal heat production

Decrease thyroxin = decrease basal heat production

16

autonomic response to heat loss

1. heat flow to skin
2. sweating

17

heat flow to the skin

SNS control of vasoldilation can increase/derease the amount of blood that flows to the skin

Increase = heat loss

Decrease = heat gain

18

Sweating

SNS control of eccrine glands can increase or decrease the amount of sweat secreted

Increase sweat = increase heat loss

19

Endocrine response to heat loss

Aldosterone

20

Aldosterone results in

1. Promotes Na+ reabsorption
2. More dilute sweat
3. Decreased tonicity of sweat = blood becomes hypertonic faster during sweating = more rapid onset of thirst = less likely to become dehydrated
4. Occurs in heat-adapted people