the nervous system

Question 1

list the parts of the nervous system

Answer 1

The central nervous system consists of the brain and the spinal cord. The peripheral nervous system however, is made up of all of the nerves that send impulses to the brain and spinal cord and away from them.

Question 2

describe how the nervous system detects stimuli

Answer 2

Receptor cells detect a change in the environment (a stimulus) and start electrical signals along neurons.

Question 3

describe the structure of sensory neurons

Answer 3

a long dendron, a cell body placed centrally and a short axon.

Question 4

describe the routes that impulses take to and from the brain

Answer 4

an impulse is then transmitted down the sensory neurone to the CNS. Relay neurone – in the CNS, there is a synapse and a relay neurone takes it through the CNS.

Question 5

explain how sensory neurons are adapted to their function

Answer 5

they have a long fibre ( axon close axonThe long part of a nerve cell along which the electrical signal quickly moves.) so they can carry messages up and down the body over long distances - the axon is insulated by a fatty (myelin) sheath -the fatty sheath increases the speed of the nerve impulses along the neuron