The Nervous System

Question 1

Sense organs detect …

Answer 1

Stimuli

Question 2

What is a stimulus? Therefore humans need to…

Answer 2

A change in your environment which you made need to react to. You need to be constantly monitoring what is going on so you can respond if you need to.

Question 3

Name the 5 sense organs. What do they all contain?

Answer 3

Eyes, Ears, Nose, Tongue, Skin

Receptors

Question 4

What are receptors?

Answer 4

Groups of cells which are sensitive to a stimulus. They change stimulus energy (eg light energy) into electrical impulses

Question 5

A stimulus can be…(7)

Answer 5

Light, Sound, Touch, Pressure, Chemical

Or a change in Position or Temperature

Question 6

Describe the receptors in the eyes

Answer 6

Light receptors - sensitive to light. These cells have a nucleus, cytoplasm and cell membrane

Question 7

Describe the receptors in the ears

Answer 7

Sound receptors - sensitive to sound. Also ‘balance’ receptors - sensitive to changes in position

Question 8

Describe the receptors in the nose

Answer 8

Smell receptors - sensitive to chemical stimuli

Question 9

Describe the receptors in the Tongue

Answer 9

Taste receptors - sensitive to bitter, salt, sweet, sour plus savoury - chemical stimuli

Question 10

Describe the receptors in the Skin

Answer 10

Sensitive to touch, pressure, pain and temperature channge

Question 11

Describe Sensory neurones

Answer 11

The nerve cells that carry signals as electrical impulses from the receptors in the sense organs to the central nervous system.

Question 12

Describe Relay neurones

Answer 12

The nerve cells that carry signals from the sensory neurones to motor neurones

Question 13

Describe motor neurones

Answer 13

The nerve cells that carry signals from the central nervous system to the effector muscles or glands

Question 14

Describe Effectors

Answer 14

Muscle and glands. Muscles contract in response to a nervous impulse, whereas glands secrete hormones

Question 15

What is the abbreviation for the central nervous system.

Answer 15

CNS

Question 16

CNS is where all the information from the sense organs is [ ] and where [ ] and actions are [ ].

Answer 16

Sent
Reflexes
Coordinated

Question 17

What does the CNS consist of?

Answer 17

The brain and the spinal chord

Question 18

What transmits information (as electrical impulses) very quickly to and from the CNS.

Answer 18

Neurones (Nerve cells)

Question 19

“Instructions” from the CNS are sent to the [ ] which respond accordingly.

Answer 19

Effectors