Nervous System

Question 1

What does the human nervous system consist of

Answer 1

The central nervous system (CNS) and peripheral nervous system (PNS)

Question 2

What is the CNS?

Answer 2

The brain and spinal chord

Question 3

What is the PNS?

Answer 3

Nerve cells that carry information from or to the CNS

Question 4

What is information carried by?

Answer 4

Nerves which are bundles of neurons

Question 5

What are neurons?

Answer 5

Long cells that carry electrical signals

Question 6

What’s the gap called where neurons meet?

Answer 6

The synapse

Question 7

How do signals pass the synapse?

Answer 7

Chemically to the next neuron, where the electrical pulse continues

Question 8

What is a receptor

Answer 8

A sense organ

Question 9

What is an effector

Answer 9

A muscle or gland

Question 10

What is the coordinator

Answer 10

The brain or spinal chord

Question 11

How does information flow form receptors to effectors

Answer 11

From the receptor, via sensory neurons, to the coordinator, and then through motor neurons to the effector

Question 12

What are the changes in the world around us to our nervous system

Answer 12

Stimuli

Question 13

What do sense organs contain

Answer 13

Specialised cells called receptor cells

Question 14

What are reflex actions?

Answer 14

A protective and automatic response to a stimulus

Question 15

How are reflex actions different to normal ones?

Answer 15

They bypass the brain, and are coordinated by the spinal chord

Question 16

What is the name for the nerve pathway in a reflex action?

Answer 16

A reflex arc

Question 17

What is involved in a reflex arc?

Answer 17

stimulus → receptor → sensory neurone → relay neurone → motor neurone → effector → response

Question 18

What is the eye?

Answer 18

A sensory organ controlled by light

Question 19

Sorry can you try and memorize this :D

Answer 19

Question 20

Cornea

Answer 20

Clear area of the sclera, it refracts light - bends it as it enters the eye.

Question 21

Iris

Answer 21

Muscles which alter the size of the pupil, controlling the amount of light entering the eye.

Question 22

Lens

Answer 22

Focuses light onto the retina.

Question 23

Retina

Answer 23

Contains the light receptor cells.

Question 24

Optic nerve

Answer 24

Carries impulses between the retina and the brain.

Question 25

Sclera

Answer 25

White, tough outer layer.

Question 26

Choroid

Answer 26

Pigmented middle layer with many blood vessels. It absorbs light to avoid reflection and nourishes the retina.

Question 27

Blind spot

Answer 27

Where the optic nerve leaves the retina so lacks receptor cells.

Question 28

Pupil

Answer 28

Small hole at the centre of the iris through which light enters the eye.

Question 29

How does information flow from receptors to effectors?

Answer 29

• Stimulus
• Receptor
• Sensory neuron
• Relay neuron
• Motor neuron
• Efector
• Response