Skin and temperature regulation

Question 1

What is meant by man being homeothermic?

Answer 1

likes to keep body temperature around the same point

Question 2

Core body temp

Answer 2

37+/-0.5

Question 3

What happens if body temperature is above 41?

Answer 3

denature proteins

Question 4

What happens if body temperature is below 30?

Answer 4

lose consciousness

Question 5

List 4 things body temperature varies with

Answer 5

menstrual cycle
circadian rhythm
external temperature
activity

Question 6

What is the biggest source of heat loss?

Answer 6

radiation

Question 7

What receptors detect temperature changes?

Answer 7

cold and warm thermoreceptors

Question 8

Where are peripheral thermoreceptors found?

Answer 8

skin eg face and scrotum

Question 9

Where are central thermoreceptors found?

Answer 9

spinal cord, abdominal organs and hypothalamus

Question 10

4 ways in which heat generated increases

Answer 10

metabolism
muscle activity
shivering thermogenesis
non shivering thermogenesis

Question 11

Who is non shivering thermogenesis important in and why?

Answer 11

infants - brown adipose tissue

Question 12

2 ways in which heat loss is decreased

Answer 12

vasomotor - sympathetic arteriolar constriction

behaviour eg add clothes

Question 13

Define hypothermia

Answer 13

A fall in deep body temperature to below 35 degrees

Question 14

Who is at risk of hypothermia?

Answer 14

neonates
elderly
vagrants
outdoor

Question 15

Treating hypothermia

Answer 15

dry/insulate
slow rewarming with blankets
internal re-warming with hot drinks
fast re-warming by immersion in water

Question 16

Vascular frostbite

Answer 16

vasoconstriction, increase in viscosity and thrombosis leading to anoxia

Question 17

Cellular frost bite

Answer 17

ice crystals form in ECF
increase ECF osmolarity
move water into space leading to cell dehydration and death

Question 18

Why is there more strokes and heart attacks in winter?

Answer 18

increased vasoconstriction and increased blood viscosity

Question 19

2 ways in which heat production is minimised

Answer 19

decrease physical activity

decrease food intake

Question 20

3 ways heat loss increased from body

Answer 20

vasomotor control - arteriolar dilation
sweating
behaviour eg remove clothes and increase surface area

Question 21

What temperature does heat exhaustion occur?

Answer 21

37.5-40 degrees

Question 22

What happens in heat exhaustion?

Answer 22

vasodilation and drop in central blood volume

excess sweating disturbs water and salt balance

Question 23

Symptoms of heat exhaustion

Answer 23

headache, confusion, nausea, profuse sweating, clammy skin, tachycardia, hypotension, weak pulse, fainting and collapse

Question 24

Heatstroke body temperature

Answer 24

above 40

Question 25

Symptoms of heat stroke

Answer 25

hot dry skin and circulatory collapse

Question 26

Most at risk groups of heat stroke

Answer 26

neonate and elderly physical work in hot climate non-breathable protective clothing

Question 27

Treatment of heat stroke

Answer 27

``` move to cool environment remove clothing fan sponge with slightly warm water give fluids - IV and oral ```

Question 28

What causes fever?

Answer 28

endogenous pyrogens

Question 29

What happens to produce fever in infection and explain why paracetomol works

Answer 29

cyclo-oxygenase in hypothalamus produces prostaglandins paracetomol blocks this enzyme Body temperature set around a higher temp endogenous pyrogens shift the set point