Skin And Temperature Regulation

Question 1

What is the normal core body temperature?

Answer 1

37 +/- 0.5

Question 2

Why does our core body temperature have to stay within a narrow range?

Answer 2

Because over 41 degrees proteins start to degenerate

And below 30 degrees we start to lose conciousness

Question 3

Where are the central and peripheral thermoreceptors located?

Answer 3

Central - spinal cord, abdominal organs, hypothalamus

Peripheral - skin, especially face and scrotum

Question 4

Where does information from the peripheral and central thermoreceptors send information to?

Answer 4

Hypothalamic thermoregulatory center

Question 5

How is heat that is generated by the body increased?

Answer 5

General metabolism
Voluntary muscular activity
Shivering thermogenesis
Non shivering thermogenesis (infants)

Question 6

How is heat loss from the body reduced?

Answer 6

Vasomotor control - sympathetic arteriolar constriction reducing delivery of blood to the skin
Behavioural reponses

Question 7

What is hypothermia ?

Answer 7

Drop in core body temp below 35

Question 8

Who are at risk of hypothermia?

Answer 8

Neonates
Elderly
Cols store workers
Outdoor pursuits
North sea workers etc

Question 9

What is the treatment for hypothermia?

Answer 9

Dry / insulate to prevent further heat loss
Slow re warming with blankets
Fast re warming by immersion in water
Internal re warming with hot drinks / warm air

Question 10

How does frost bite occur as a response to cold stress?

Answer 10

Cold causes vasoconstriction and incrreased viscosity which promotes thrombosis = anoxia
Ice crystals form in the extracellular spaces which increases extracellular osmolarity. This causes movement of water from intracellular space = cell dehydration & death

Question 11

Why is there an increase in strokes and heart attacks in the winter months?

Answer 11

Cold weather = vasodilatation and increased viscosity = thrombosis = ischaemia

Question 12

How is heat production minimised?

Answer 12

Reduced food intake

Decreased physical activity

Question 13

How is heat loss from the body increased?

Answer 13

Vasomotor control - arteriolar dilation
Sweating - sympathetic cholinergic fibres increase evapourative heat loss
Behavioural responses

Question 14

At what body temperature results in heat exhaustion?

Answer 14

37.5 - 40

Question 15

How does heat exhaustion occur?

Answer 15

Body temperature rises there is a disturbance in the bodys fluid/salt balance due to excessive sweating

Question 16

What are the symptoms of heat exhaustion?

Answer 16

Headache
Confusion
Nausea
Profuse sweating
Tachycardia
Hypotenion (arteriolar dilatation = drop in central blood volume)
Clammy skin
Weak pulse 
Fainting & collapsing

Question 17

What is heat stroke?

Answer 17

Body temperature raised above 40 and it causes the bodys temperature control mehcnaisms to fail

Question 18

What are the symptoms of heat stroke?

Answer 18

Hot, dry skin

Circulatory collapse

Question 19

Who are most at risk of heat stroke / heat exhaustion?

Answer 19

Neonates and elderly

People doing physical work in humid environments

Question 20

What is the treatment for heat stroke?

Answer 20

Fluids
Fan
Sponge with tepid water

Question 21

What is repsonsible for causing fever when our body is fighting infection?

Answer 21

Endogenous pyrogens

They cause local production of prostaglandin’s by cyclo-oxygenase in the hypothalamus