Skin and Temperature Regulation

Question 1

What is the core body temperature?

Answer 1

37 degrees +/- 0.5 degrees

Question 2

When do proteins start to denature?

Answer 2

41 degrees Celsius

Question 3

When do humans begin to lose consciousness?

Answer 3

Below 30 degrees

Question 4

Define convection?

Answer 4

Fluid conduction hence why wind chill or water chill occurs

Question 5

How does evaporation affect thermal balance?

Answer 5

Respiration and swearing causes 600ml of evaporation to occur. 4l/hour loss occurs at extremes

Question 6

How does conduction affect thermal balance?

Answer 6

Heat transfer direct between touching objects

Question 7

How does radiation affect thermal balance?

Answer 7

60% of heat is lost

Question 8

Where are peripheral thermoreceptors located?

Answer 8

Located in the skin, especially in face and scrotum

Question 9

Where are central thermoreceptors located?

Answer 9

Spinal cord, abdominal organs, hypothalamus

Question 10

What do peripheral thermoreceptors detect?

Answer 10

Changes in environmental temperature?

Question 11

What do central thermoreceptors detect?

Answer 11

A change in core body temperature

Question 12

How is heat generated within the body in response to cold stress?

Answer 12

General metabolism increases heat by oxidative phosphorylation, voluntarily moving muscles, shivering thermogenesis and nonshivering thermogenesis in brown adipose tissue in infants

Question 13

How is heat lost from the body during cold stress?

Answer 13

Vasomotor control - arteriolar constriction reduces delivery of blood to the skin, Behavioural Response causes us to add clothing or move to warmer environments

Question 14

Who is at risk for hypothermia?

Answer 14

Neonates, Elderly, vagrants, cold store workers, north sea workers, outdoor pursuits

Question 15

How is hypothermia treated?

Answer 15

Dry/Insulate to prevent heat loss, slow re-warming with bag/blankets, internal re-warming with hot drinks and/or warm air, fast re-warming by immersion in water, extracorporeal circulation

Question 16

What is the vascular cause of frost bite?

Answer 16

Vasoconstriction, increase in viscosity, promotes thrombosis, causes anoxia

Question 17

What is the cellular cause of frost bite?

Answer 17

Ice crystals form in Extracellular Space, increases extracellular osmolality, causes movement from Intracellular Space and this causes dehydration and death

Question 18

What occurs in heat exhaustion?

Answer 18

Body temp raises to 37.5-40 degrees, results in vasodilation and drop in central blood volume. Is caused by a disturbance of the body’s fluid/salt balance due to excessive sweating.

Question 19

What are the symptoms of heat exhaustion?

Answer 19

Headache, confusion, nausea, profuse sweating, clammy skin, tachycardia, hypotension, weak pulse, fainting and shock

Question 20

What occurs in heat stroke ?

Answer 20

Body temp rises above 40 degrees, body temp control mechanisms fail,

Question 21

What are the symptoms of heat stroke?

Answer 21

Hot dry skin and circulatory collapse

Question 22

Who are most at risk of heat stress?

Answer 22

Neonates and the elderly, labourers in hot weather

Question 23

What is a fever?

Answer 23

Part of the bodys mechanism for fighting infections caused by endogenous pyrogens (IL-1, IL-6)