nervous system Flashcards
what is a stimulus
a change in environment
how can a stimulus be recognised
by a receptor
what happens if a receptor is stimulated
it may cause an effector (muscle/gland) to produce a response
how do you respond to the environment
with a co-ordinator
what does the co-ordinator do
links the receptors and effectors
what is the co-ordinator
usually the brain and spinal cord
what makes up the Central Nervous System
brain and spinal cord
what do neurones do and what are they
link the receptors and effectors to the co-ordinator
they are nerve cells
how do neurones carry information
in the form of small electrical charges called nerve impulses
name the three types of neurones
Sensory
relay
motor
what does sensory link with
receptor to cns
what does relay link with
within cns
what does motor link with
cns with effector
what is the reflex arc
short pathway through the spinal cord
what is the function of receptors in the reflex arc
detect stimulus and passes impulses to sensory neurone
describe reflex arc
- a sensor picks up stimulus
- impulse passed along sensory neurone from receptors in hand to spinal cord
- cell body of sensory neurone is on a short side branch in a swelling in dorsal root
- impulse-> grey matter passes over synapse
- passes then to a relay neurone
- passes to motor and leaves spinal cord through ventral root and continues into effector
what is a hormone
a chemical produced in one part of the body that exerts its effects elsewhere
where is the hormone transported
bloodstream
how is the hormone produced
by glands
what is insulin
is the hormone that prevents blood glucose levels from becoming high
what will too much glucose in the blood cause
water to leave cells
where is insulin produced
pancreas
what does the pancreas do
constantly monitors blood glucose concentration
what is the target organ for insulin
liver
