The Reflex arc.
Answer the questions in your book:
1. Name the parts of the neurone:
A B C D
E F
2. Give 2 ways in which a neurone is adapted for its function.
3. How does information pass along a neurone?

Lesson Objective:
To develop an understanding of the reflex arc.
Learning outcomes
Be able to describe the pathway of a nerve impulse in a response to a stimulus.
Be able to describe the pathway of a nerve impulse in a reflex arc.
Be able to give some examples of reflexes and explain why reflexes are useful.

Neurones
Nerves are made up of hundreds of nerve cells called neurones.

Neurones
Neurones transfer information to and from the
CNS.
There are three types:
Sensory neurone
Relay neurone
Motor neurone

In organisms, effectors can be either muscles or glands.
Contract Release hormones

Neural Pathway
This is the path taken through the nervous system from stimulus to response.

Neural Pathway

Neural Pathway

Neural Pathway
When muscles are stimulated with an electrical impulse from the nervous system they will…
When glands are stimulated with an electrical impulse from the nervous system they will…

Lesson Objective:
To develop an understanding of the reflex arc.
Learning outcomes
Be able to describe the pathway of a nerve impulse in a response to a stimulus.
Be able to describe the pathway of a nerve impulse in a reflex arc.
Be able to give some examples of reflexes and explain why reflexes are useful.

Reflexes
Reflex actions are actions that happen very quickly in the body.
They bypass the conscious part of the brain and are coordinated by the spinal cord .
The result of this is that the time between the stimulus and the reflex is as short as possible .

Reflexes

Reflexes
Complete the sheet to show the reflex arc:

Reflexes

Lesson Objective:
To develop an understanding of the reflex arc.
Learning outcomes
Be able to describe the pathway of a nerve impulse in a response to a stimulus.
Be able to describe the pathway of a nerve impulse in a reflex arc.
Be able to give some examples of reflexes and explain why reflexes are useful.

Reflexes
Response Reason for response
Stimulus
Tap the knee
Shine light into eyes
Clap hands in front of the face

Advantage of reflexes
What do you think the advantage of bypassing the conscious part of the brain to make the time between the stimulus and the reflex is as short as possible?

Answer the questions in your book:
1. Reflexes bypass which part of your brain?
2. Why are reflexes important?
3. What makes reflexes faster than other neural pathways?
4. Give 2 examples of where we use reflexes.