Synapses and Reflexes

Question 1

What do neurones do?

Answer 1

Transimit information (as electrical impulses) very quickly to and from the CNS

Question 2

Reflexes are ____ than neurone transmission to the brain and decisions made from there

Answer 2

Reflexes are quicker than neurone transmission to the brain and decisions made from there

Question 3

What is a synapse?

Answer 3

The connection between two neurones

Question 4

Describe how nerve signals are transferred across a synapse

Answer 4

The nerve signal is transferred by chemicals which diffuse across the gap.

These chemicals then set off a new electrical signal in the next neurone

Question 5

Reflexes help prevent ____

Answer 5

Reflexes help prevent injury

Question 6

Define ‘reflexes’

Answer 6

Automatic responses to certain stimuli

Question 7

Describe the reflex caused by shining a bright light in your eye

Answer 7

The pupil automatically gets smaller to prevent the light getting into the eye and causing damage to the retina.

Question 8

Describe the reflex caused by getting a shock

Answer 8

Your body automatically releases the hormone adreniline

Question 9

What is the passage of information in a reflex called?

Answer 9

A reflex arc

Question 10

What is the span of a reflex arc?

Answer 10

From receptor to effector

Question 11

Electrical impulses travel from neurone to neurone ____ ____.

Why is this important?

Answer 11

Electrical impulses travel from neurone to neurone really fast.

This gives you a chance of being able to respond quickly to stimuli

Question 12

A reflex arc can travel through which 2 parts of the CNS?

Answer 12

1. The spinal chord
2. An unconcious part of the brain

Question 13

Describe 7 the steps to a reflex arc

Answer 13

1. A stimulus is detected by receptors
2. Impulses are sent along a sensory neurone to the CNS
3. When the impulse reaches a synapse between the sensory neurone and a relay neurone, they trigger chemicals to be released.
4. These chemicals cause impluses to be sent along the relay neurone.
5. When the impulse reaches a synapse between the relay neurone and a motor neurone, they trigger chemicals to be released.
6. These chemicals cause impluses to be sent along the motor neurone to the effector.
7. The effector then responds.

Question 14

If a bee stings your finger, name the stimulus and the effector and response

Answer 14

Stimulus = pain from bee sting

Effector = muscle

Response = to contract

Question 15

What are the 7 steps for a reflex arc?

Answer 15

1. Stimulus
2. Receptor
3. Sensory neurone
4. Relay neurone
5. Motor neurone
6. Effector
7. Response

Question 16

What do reflexes do, and when?

Answer 16

Reflexes bypass your concious brain completely when a quick response is essential

Question 17

What reflex arcs be used to do in medicine?

(2)

Answer 17

To asses the conditions of:

1. Unconcious casualties

or

2. Those with spinal injuries

Question 18

Which bodily system are doctors examining when they tap your knee with a hammer and check that you kick?

Answer 18

Reflex arcs