Skin And Temperature Regulation

Question 1

What is the normal core body temperature?

Answer 1

37 +/- 0.5 degrees Celsius

Question 2

Actions that keep the body in thermal balance?

Answer 2

Convection (fluid conduction),
Conduction (heat transfer),
Evaporation (respiration and sweating),
Radiation

Question 3

Where do you find peripheral receptors and what do they respond to?

Answer 3

Located in the skin, especially the face and scrotum,

They respond to changes in environmental temperature

Question 4

Where would you find central thermoreceptors are what do they respond to?

Answer 4

In the spinal cord, abdominal organs and hypothalamus, respond to changes in core body temperature

Question 5

How does the body respond to cold stress, with regards to generating heat?

Answer 5

It uses general metabolism,
voluntary muscular activity,
Shivering thermogenesis,
Nonshivering thermogenesis

Question 6

How does the body respond to cold stress with regards to reducing heat loss by body?

Answer 6

Vasomotor control (sympathetic arteriolar constriction reduces delivery of blood to skin),
Behavioural responses (more layers, reduce surface area, moving to warmer environment)

Question 7

What is hypothermia?

Answer 7

Fall in deep body temperature to below 35degress

Question 8

What is vascular frost bite?

Answer 8

Vasoconstriction causes an increase in viscosity which promotes thrombosis and causes anoxia

Question 9

What is cellular frost bite?

Answer 9

Ice crystals form in extracellular space and increase extracellular osmolality, this causes a movement of water from intracellular space, which causes cell dehydration and death

Question 10

How is heat production minimised?

Answer 10

Decreased physical activity and decreased food intake

Question 11

How does the body respond to heat stress with regards to increasing heat loss?

Answer 11

Vasomotor control (arteriolar dilation increases delivery of blood to the skin)
Sweating (sympathetic cholinergic fibres increase evaportive heat loss),
Behavioural responses (increasing surface area, moving to shaded area)

Question 12

What is heat exhaustion/ heat illness)

Answer 12

When the body temperature raises in range of 37.5-40degrees, causing vasodilation and drop in central blood volume, due to excessive sweating disturbaning body’s fluid/ salt balance

Question 13

Symptoms of heat exhaustion/ heat illness?

Answer 13

Headache,
Confusion, 
Nausea,
Profuse sweating, 
Clammy skin,
Tachycardia,
Hypotension,
Weak pulse, 
Fainting and collapse

Question 14

What is heat stroke/ heat injury?

Answer 14

When the body temperature raises above 40degrees, this causes the body’s temperature control mechanisms to fail

Question 15

Symptoms of heat stroke (heat injury)?

Answer 15

Hot dry skin (sweating ceased) and circulatory collapse

Question 16

What is a fever?

Answer 16

Part of body’s mechanism for fighting infection, caused by endogenous pyrogens, the endogenous pyrogens shift the temperature set point in the hypothalamus

Question 17

How do endogenous pyrogens change the body temperature?

Answer 17

There is local production of prostaglandins by cyclo-oxygenase in the hypothalamus, which causes a shift in the set temperature point, like changing a thermostat