Nervous system part 4 Flashcards
what is thermoregulation
control temperature. the body must maintain an average body temperature of 37 degrees celsius.
explain the increase in temperature
- thermo receptors in hypothalamus detect the increase.
- blood vessels dilate (vasodilation)
- more blood in contact with skin and more heat radiated
- sweat glands are stimulated to release more sweat.
- sweat evaporated and cools the body down.
- body temperature decreases
explain decrease in temperature
-thermo receptors in hypothalamus detect the decrease
- blood vessels constrict (vasoconstriction)
- less blood in contact with skin and less heat radiated
- muscles are activated to shiver
- hair follicles activated to trap more heat
- body temperature increase
the skin is the biggest organ.
name the functions
protects internal organs
controls body temperature
sense of touch
how do we feel
receptors in skin is stimulated
stimuli converted into electrical impulse
sensory neuron conduct impulses to brain
cerebrum interprets the feeling
when blood vessels construct it is called?
vasoconstriction
when blood vessels dilate it is called?
vasodilation
Stimulants
increase the heat rate/ blood pressure/ breathing rate.
cocaine
causes the release of a chemical called dopamine which produces feelings of pleasure . when it wears off the person feels sad & depressed as the dopamine is depleted.
Dagga
produces a temporary feeling of happiness.
bad for lungs
can lead to memory loss
can lead to inability to concentrate
reduced level of testosterone in males
alcohol
slows down reflexes and coordination
affects judgement
leads to alcohol related accidents (car)
women who drink alcohol can have babies with:
foetal alcohol syndrome (FAS)
mental/physical abnormalities
