The Nervous System

Question 1

What is homoestasis?

Answer 1

The maintenance of a constant internal environment at optimal conditions

Question 2

What is a receptor?

Answer 2

Cells which detects stimuli/change in the environment e.g temperature, light levels etc.

Question 3

Where does the signal that is sent by the receptor go and where after that?

Answer 3

Coordination center, which will pass the signal on to an effector

Question 4

What happens to the stimulus after being detected by a receptor cell?

Answer 4

The stimulus is changed into an electrical signal by the receptor cell

Question 5

Where does the signal go after being transformed from stimulus to signal?

Answer 5

The Nervous System sends this signal along neurons

Question 6

How are neurons specialised?

Answer 6

to be conductive of electrical charges and to branch and form numerous connections within the body

Question 7

Whatt type of neurons found between receptors and coordination center?

Answer 7

Sensory neurons

Question 8

How do sensory neurons respond to in the skin and eyes?

Answer 8

Eyes=light
Skin=pressure, temperature changes

Question 9

What type of neurons is found between coordination centre and effector?

Answer 9

Motor neurons

Question 10

What is the coordination centre made up of and what do they form?

Answer 10

Brain and spinal cord, which form the central nervous system?

Question 11

What happens once the effector receives the signal?

Answer 11

A response will be generated

Question 12

What is the spine divided in?

Answer 12

Vertebraes

Question 13

Where does the signal go in sensory neurons in a reflex?

Answer 13

To the spinal cord (in a vertabrae)

Question 14

What connects the sensory and motor neurons in the spine and what does it do?

Answer 14

Relay neuron, ensure the message passes onto the correct motor neuron

Question 15

What is a motor neuron connceted to in a reflex?

Answer 15

To the effector, either:

Gland that will release a chemical e.g hormone

Muscle, which will contract or relax, in this case contract to get smaller to pull the hand from in this case the heat source

Question 16

Why are reflexes important?

Answer 16

The communication loops around the spine rather than travelling all the way up to the brain to be consciuosly processed

This process is quick and automatic, reducing damage

Question 17

What are some other reflexes?

Answer 17

Blinking
Breathing
Sneezing

Question 18

What is triggered in by the nerve impulse in the synapse?

Answer 18

The release of chemical, neutransmitter molecules that are packaged in circle like-shapes

These are sitting waiting to receive that nerve impulse

Question 19

What do packages of neutransmitter do?

Answer 19

They move towards the membrane of the end of that neuron and they actually fuse with it

This causes them to open up to allow neutransmitter chemicals inside them to be released

These diffuse across the synapse

Question 20

What happens to neurotransmitter molecules when diffused in synapse?

Answer 20

They dock into receptor molecules located at the start of the next neuron

Another electrical impulse will be generated

Question 21

What is the electrical signal converted in across a synapse?

Answer 21

Chemical signal

Question 22

What is time equal to in the required practical?

Answer 22

Square root of 2xdistance (m)
- - - - - - - - - - - - - - - - - -
Acceleration 9.81m/s*2

Question 23

What is another way to investigate reaction time?

Answer 23

Computer simulation