coordianation and response- key terms Flashcards
Define central nervous system (CNS)
consists of the brain and spinal cord, which are the areas of coordination.
Define peripheral nervous system (PNS)
comprises nerves and neurones, which coordinate and regulate body functions.
types of neurones: define nerve impulse
an electrical signal that passes along the nerve cells called neurones
types of neurones: define axons
Ensure less time is wasted when the impulse is transferred from one neurone to another
types of neurones: define dendrities
Extensions which form a network for easy communication.
types of neurones: define motor neurone
Carry impulses from the CNS to effectors (muscles or the glands)
types of neurones: define sensory neurone
Carry impulses from the sense organs (sensory receptors) to the CNS.
types of neurones: define relay neurone (Interneurone)
The middleman inside the CNS connects sensory to motor neurones.
Define reflex action
automatically and rapidly integrates and coordinates the stimuli with the responses of effectors (muscles and glands).
Define synapse
a junction between two neurones, consisting of a gap across which impulses pass by diffusion of a neurotransmitter
Define sense organ
groups of receptor cells responding to specific stimuli: light, sound, touch, temperature, and chemicals
Define cornea
refracts light
Define Iris
controls how much light enters the pupil
Define lens
focuses light onto the retina
Define retina
contains light receptors, some sensitive to light of different colours (Rods and cones)