response and regulation Flashcards
what are the body sense organs and what doe they sense
eye-light
nose -chemical smell
tongue-chemical taste
ears -sound
skin- temperature pressure touch and pain
muscle -tension
what are sense organs made out of
receptor cells these detect changes around them either internally or in the external environment
hat are changes called
stimuli these are the changes in the environment
hat is the cns
spinal cord and brain
hat are examples of a reflex action
pupil reflex sneezing
cornea
transparent layer of the eye and it refracts light
iris
controls the size the size of the pupil the coloured part of the eye
pupil
is the gap in the iris that allows light rays to enter
lens
focuses light in to the retina
choriod
black pigmented layer absorbs light preventing internal reflection
scalera
tough white protective outer layer
maintains the eyeball shape
retina
light sensitive layer
Impulses sent to optic nerve.
blind spot
Where the optic nerve connects to the retina; there are no light-sensitive cells here.
optic nerve
Optic nerve Carries impulses from retina to brain.
nerve cells can
also be called neurones
what happens if you touch a hot plate
If you touch a hot plate, you move your hand away quickly. The following sentences describe what happens:
Receptors in the skin detect that the plate is hot.
Electrical impulses travel along sensory neurones to the spinal cord.
The spinal cord sorts out the information. It is called the co-ordinator.
Impulses from the spinal cord travel along motor neurones to the arm muscle (effector).
A muscle in the arm contracts, moving it away from the hot plate.
what is the coordinator
effector and receptor
the spinal cord
the muscle
the skin
what is a tropism
these are growth responses of a plant to ward a stimulus
the response of a plant downwards toward gravity
is called positive gravtropism
t does homeostasis mean
Homeostasis is the maintenance of a constant internal environment to keep conditions at an optimum
when you are too hot
hen we are too hot
The hairs lie flat, so there is no insulating layer of trapped air.
The sweat gland produces sweat. The sweat travels up the sweat duct and passes out onto the skin’s surface through the sweat pore. This cools you down when the sweat evaporates.
The blood vessels near the skin’s surface dilate. This brings more blood nearer to the surface and so more heat energy is lost by radiation.
when you are too cold
When we are too cold
The erector muscles contract to make the hairs stand on end. This traps an insulating layer of air.
Less or no sweat is released from the sweat gland.
The blood vessels near the skin’s surface constrict. This means less blood is near the skin’s surface and so less heat energy is lost by radiation.
we shiver, which generates heat through muscle contraction. The muscles carry out more respiration and therefore more heat energy is released in the body.
what are hormones
they are chemical messengers
produced by glands and carried by the blood the are all proteins
when insulin rises
If your blood glucose rises after a meal, your pancreas releases proteins called hormones. The hormone released when blood glucose rises is called insulin. Insulin is released by the pancreas and travels in the blood to its target organ – the liver. Insulin causes the liver to reduce the blood glucose level by converting the glucose to insoluble glycogen and then storing it.
