Nervous System

Question 1

What does central nervous system consist

Answer 1

Brain + spinal cord (relay neurones)

Question 2

What peripheral nervous system ?

Answer 2

All the nerve in the body (sensory and motor neurons)

Question 3

Neurons

Answer 3

Nerve cell that transmit nerve signal to and fro the brain

Question 4

Dendrites function

Answer 4

Branches that function as signal receivers

Question 5

Cell body function

Answer 5

Spherical part of the neuron that contains the nucleus

Question 6

Axon description

Answer 6

Long extension part which takes info away from the cell body

Question 7

What is sensory neurons function (PNS)

Answer 7

Carry messages from the body sense receptors to the CNS

Question 8

What is relay neurons (CNS)

Answer 8

Carry messages from one part of the CNS to another

Question 9

What motor neurons (PNS)

Answer 9

Carry signals from the CNS to the muscles and glands

Question 10

Sensory dendrites, axons and overall

Answer 10

Long

Short

Long

Question 11

Relay dendrites, axons and overall

Answer 11

Short

Short

Short

Question 12

Motor dendrites, axons and overall

Answer 12

Short

Long

Medium

Question 13

Reflex action

Answer 13

Involuntary response to the stimulus

Fast to avoid the pain or cause harm

Question 14

Reflex action

Answer 14

Stimulus

Pain receptor stimulated

Signal sent along - sensory neuron

Signal passed along relay neuron (message sent to brain)

Signal sent along motor neuron

Effector muscle contracts (response)

Question 15

Define synapse

Answer 15

Junction that neuron forms with another cell for communication

Question 16

Function nervous

Answer 16

Nervous system - uses both electrical and chemical signals

Question 17

The synapse process

Answer 17

1) an electrical impulse travels along an axon (presynaptic neuron)

2) this triggers the nerve ending of a neuron to release chemical messengers called neurotransmitters

3) these chemical diffuse across the synaptic cleft and bind with receptor molecule on the membrane of the next neuron (postsynaptic neuron)

4) the receptor molecule on the postsynaptic neuron. This stimulates the postsynaptic neuron to transmit the electrical impulse