The nervous system

Question 1

What do organisms need to do in order to survive?

Answer 1

• respond to stimuli

Question 2

single celled organism can just —- to its —-
but what do multi cellular organisms need to do?

Answer 2

• respond, environment
• need to communicate with each other first so as they evolve, they develop nervous and hormonal communication systems

Question 3

Define the nervous system

Answer 3

• It comprises of millions of neurons that go to all parts of the body
• The nervous system carries electrical impulses that travel very fast
• These impulses mean that the body can respond to its environment very quickly

Question 4

Different parts that make up the nervous system

Answer 4

CNS
- in vertebrates, this consists of brain and spinal cord only
-in mammals, CNS is connected to the body by sensory neurons and motor neurons

Question 5

Different parts that make up the nervous system

Answer 5

• sensory neurone carry info as electrical impulses from receptor to the CNS
• motor neurone carries electrical impulses from CNS to effector
• Effector
  all your muscle and glands will respond to nerve impulses

Question 6

Different types of receptors and what can receptors form?

Answer 6

visual hearing, taste smell skin, balance
- form part of larger complex organs

Question 7

How do effector muscle and gland respond?

Answer 7

Muscle contracts and gland secretes hormones

Question 8

What is the CNS?

Answer 8

example of coordination centre, receives info from receptor and coordinates a response. response then carried out by effector

Question 9

Stages bird goes through when it spots a cat
(example)

Answer 9

-stimulus
- receptor (in eye is stimulated)
- sensory neurone
- CNS
- motor neurone
- effector
- response