SB2G Nervous System

Question 1

List the parts of the nervous system

Answer 1

The nervous system consists of the brain, spinal cord, sensory organs, and all of the nerves that connect these organs with the rest of the body.

Question 2

Describe how the nervous system detects

stimuli.

Answer 2

made up of neurones which go to all parts of body.
has lots of sensory receptors,
when stimulus is detected, information converted to impulse and sent along sensory neurones to CNS.
Receptors coordinates response, impulse travel through CNS along relay neurone, CNS sends information to effector, effector responds
time for response is called reaction time

Question 3

Describe the structure of sensory neurones.

Answer 3

Sensory neurons have dendrites on both ends and are connected by a long axon that has a cell body in the middle.

Question 4

Explain how sensory neurones are adapted to
their functions (including the myelin sheath).

Answer 4

Are long to allow fast neurotransmissions over long distances.
Fatty layer surrounding these, called myelin sheath. Insulates neurone from neighbouring neurones, stopping signal losing energy.