PHYS: Hypothalamus

Question 1

What controls the set point and core temperature of the body?

Answer 1

Hypothalamus

It recieves infor about the current temperature and decides what to do

Question 2

What is normal body temp:

Answer 2

98.6 (or 36.7 degrees in the morning)

Question 3

What are 3 types of thermoreceptors?

Answer 3

1. Cutaneous (skin)
2. Visceral
3. Hypothalamic

Question 4

Which body temperature (hands, feet, oral, core) does not change over a variety of temperatures?

Answer 4

CORE Temperature! stays the same

Question 5

Cutaneous thermoreceptors are sensitive to?

Answer 5

The cold –> they have 10x as many cold receptors, cause the biggest threat to our skin is cold temperatures

Question 6

Thermoreceptors in our gut sense?

Answer 6

food that is ingested that may change our body temperature (ex. ice cream)

Question 7

Where are thermoreceptors located in the hypothalamus?

Answer 7

Pre-Optic + Superoptic region of hypothalamus!

Question 8

Neuron thermoreceptors in the hypothalamus are sensitive to?

Answer 8

Heat! have 10x more warm receptors

Becuase in your brain, heat is your biggest threat

Question 9

Which thermoreceptors are classified as detecting “core” temperature?

Answer 9

Brain (Hypothalamus) + Viscera

Question 10

How does the hypothalamus have the ability to control the body set point?

Answer 10

Cause it can activate hormones, autonomic sympathetics, behavioral changes (shivers)

Question 11

What happens to our core temperature when we sleep + exercise?

Answer 11

When we sleep our temperature decreases (decreases in set point) and when we exercise our core temperature increases.

Question 12

The anterior hypothalamus responses to ______.

Answer 12

heat

Question 13

The posterior hypothalamus responds to ________.

Answer 13

cold

(for example. if it is cold outside the posterior hypothalamus becomes active to make me wanna warm up)

Question 14

Babies have ________ which leads to them losing heat very fast. Therefore, they need a lot of adipose tissue to insulate their tiny baby bodies :)

Answer 14

High surface area

Question 15

What area is responsible for shivering, in order to increase heat production?

Answer 15

Dorsomedial posterior hypothalamus

Question 16

How does brown adipose tissue lead to heat production?

Answer 16

Uncoupiling proteins

Question 17

How do we lose heat?

Answer 17

1. Evaporation –> insensible (respiratory) + sweating (controlled)
2. Convection –> Mvmt of molecules away from contact (heat rises)
3. Conduction–> transfer of heat w/ 2 things touching eachother
4. Radiation –> losing heat to the walls (w/out touching them)

Question 18

What determines how much heat we lose?

Answer 18

How much blood is sent to the skin determines how much heat moves from blood to external environment.

*more blood sent to skin = more heat given off = appear flushed (like me :))

Question 19

What is the innervation of a sweat gland?

Answer 19

Sympathetic cholinergic

*Instead of the usual NE, Ach is used as the neurotransmitter to bind to a muscarinic receptor

Question 20

In the process of sweating, as the blood flows next to the sweat gland, what is reabsorbed?

Answer 20

Na+, Cl-, and water

Question 21

How do we increase heat production?

Answer 21

Shivering + Non-shivering thermogenesis

Question 22

What is the definition of a fever?

Answer 22

A controlled increase in body temperature.

(the set point of the body increases)

Question 23

When we get an infection (endotoxins), our immune cells release what that helps raise our hypothalmic set point for temperature to kill them off?

Answer 23

Prostaglandin E2

Question 24

In a fever, why do we suddenly feel so cold?

Answer 24

Because our body temperature is now lower than our temperature set point.

Question 25

When the “bug” endotoxin is all gone, what happens?

Answer 25

Your hypothalamic set point returns to normal and all those blankets you were buried under now make you feel fucking hot.

Question 26

What do we do when Tb > Tset point?

Answer 26