2.1 - Thermoregulation

i love making flashcard :) put on my podcast and make my little notes

What is homeostasis?

maintaining a constant internal environment despite internal or external changes in order to maintain optimal conditions for enzyme activity

What is thermoregulation?

maintaining a relatively constant core body temperature

What is the body temperature in humans?

37 C

What is the optimum temperature for enzymes found in the body?

37 C

What is thermoregulation?

maintaining a constant internal body temperature despite internal/external changes for optimum enzyme activity

What are the risks of high temperature extremes?

heat stroke, dehydration and death

What ae the effects of high temperature extremes on enzymes?

can denature enzymes

What are the temperatures that could cause the body to overheat?

43-44 C

What are the risks of low temperature extremes?

hypothermia and death

What are the effects of low temperature extremes on enzymes?

slows down enzymes

What are the temperatures that could cause the body to freeze?

35 C

What part of the brain monitors and controls body temperature?

the thermoregulatory centre in the hypothalmus

How does the thermoregulatory centre monitor and control body temperature?

it contains temeprature receptors that are sensitive to blood temperature

How does the skin also monitor body temperature?

it contains temperature receptors that can detect temperature changes in the external enviroment and sends them to thermoregulatory centre in the brain

What is negative feedback?

a process that reverses a change in the internal enviroment

Why does negative feedback occur?

in order to bring the change back to optimal conditions and maintain a steady state in the body

How do blood vessels that supply capillaries in the skin cool down the body if you get too hot?

• blood vessels supplying skin capillaries dilate (vasodilation)

• so more blood flows closer to the surface

• more heat is lost by radiation which cools you down

How do blood vessels that supply capillaries in the skin warm up the body if you get too cold?

• blood vessels supplying skin capillaries get narrower (vasoconstriction)

• less blood flows near the skins surface

• so less neat is lost from the body

How do sweat glands cool down the body if you get too hot?

• sweat glands produce sweat

• sweat evaportates removing heat energy from your body

• this cools you down to maintain body temperature

How do sweat glands warm the body if you get too cold?

• sweat glands produce less sweat/no sweat

• so less sweat evaporates

• so less energy is transferred from the body to the surroundings

How do skeletal muscles cool down the body if you get too hot?

no shivering/spontaneous contraction

How do skeletal muscles warm the body if you get too cold?

• muscles contract + relax spontanously (shivering)

• muscle cells respire more so release more heat as this is an exothermic reaction

What is an exothermic reaction?

energy released to surroundings

How do erector pili muscles cool down the body if you get too hot?

erector pili muscles relax causing hairs to lie flat

How do erector pili muscles warm the body if you get too cold?

• these muscles contract pulling hair upwards

• this traps a layer of insulated air so less heat is lost