Thermoregulation - SB7 Flashcards
What ia the normal temperature of major organs in the human body?
(what classifies a fever and hypothermia too?)
normal: 37C
fever: 38C
hypothermia: 36C
Why are fevers and hypothermia dangerous?
they affect how well enzymes in the body work
What is the definition of thermoregulation?
The control of body temp
Where is and what is the hypothalamus?
small pat of the brain that constantly monitors temperature
How does the hypothalamus detect temperature changes?
it recieves information from temp receptors in the dermis of the skin - receptors inside the hypothalamus detect temperature changes in brain + blood
What changes occur if the hypothalamus detects a drop in temperature?
shivering, hair stand up right, reduction of blood flow near skin
what is shivering? how does it help?
when muscles start to contract and relax rapidly - the energy released from cell respiration for shivering warms you up
How do hairs stand upright? what is the effect of this on mamals?
contraction of errector muscles in the dermis of the skin - helps mamals to trap air next to skin for insulation
how does reduction of blood flow near the skin help conserve heat?
keeps warm blood deeper inside the body - this reduces the rate of transfer of energy to the air by heating
what happens if the hypothalamus detects a rise in temp?
sweating, hair lies flat, increase blood flow closer to the skin
how does sweat help to regulate body temp?
sweat spreads out as a thin layer over the skin epidermis where it evapourates - this transfers ebergy fro the skin to the surroundings by heating so skin cools down
how does blood flow increase near the surface of the skin regulate temp?
makes it easier for blood to transfer energy to the air so we cool down
what is vasoconstriction? how does it help regulate body temp?
when cold, hypothalamus sends nerve impulses to small arteries deep in the skin causing them to narrow which helps to reduce energy transfer to the surroundings
what is vasodilation? how does it help regulate body temp?
When body is hot, the hypothalamus causes small arteries to widen brining warm blood nearer to surface of the skin and increases energy transfer to the surroundings
the control of body temperature is an example of what? what is the importance of this?
negative feedback - makes sure the conditions are at the right level
