nervous system

Question 1

what are neurones

Answer 1

nerve cells adapted to carry rapid electrically changing signals to different parts of the body

Question 2

what is a cell body

Answer 2

contains the usual cell organelle but also many mitochondria, ribosomes and rer in order to manufacture neurotransmitters
what are dendrons

Question 3

what are dendrons

Answer 3

extention of the cell body which subdivides into dendrites which carry nerve signals towards the cell body

Question 4

what are axons

Answer 4

long single fibre that carry signals away from the cell body

Question 5

what are schwan cells

Answer 5

made fro mlipoprotien and surrounds the axon, wrapped around carries out phagocytosis and plays a role in nerve regeneration

Question 6

what is myelin sheath

Answer 6

covering of an axon made from membrane of the schwann cells rich in lipid myelin and those with a sheat are called myelinated neurones

Question 7

what are node of ranvier

Answer 7

constrictions between adjacent schwann cell where there are no myelin sheat

Question 8

what are sensory neurones

Answer 8

transmit nerve impulses from the receptor to intermediate or motor neurons it has a long dendron which carries impulses towards the cell body and it is unipolar

Question 9

what are motor neurons

Answer 9

carry transmit nerve impulse from relay neuron to an effector or a gland or muscle they have long axons and many dendrites

Question 10

what is a relay neurone

Answer 10

transmit nerve impulses from sensory to motot neurones and they have short branches