3.1.1 Nervous System

Learn about the nervous system (OCR Gateway A Biology GCSE)

Nervous system

An organ system that uses electrical impulses to transmit data around the body

Nervous system is made up of

• CNS

• PNS

CNS

central nervous system

PNS

peripheral nervous system

CNS consists of

brain and spinal cord

PNS consists of

all the nerves in the body

stimulus

detects change in environment

receptors

cells that detect change in the body

effectors

muscles or glands which response to impulses by contracting or releasing hormones

the eye has

photoreceptor cells

the eye is stimulated by

light

taste buds have

taste buds

taste buds are stimulated by

chemical substances

skin has

skin receptors

skin is stimulated by

pressure and temperature

nose has

olfactory receptors

your nose is stimulated by

chemical substances

Sensory neuron

a neuron which carries electrical impulses from receptor cells to CNS

Relay neuron

a neuron that carries electrical impulses from sensory neurons to motor neurons

Motor neurons

carries electrical impulses from CNS to effectors