Nerves

Question 1

sensory neuron

Answer 1

Transmits impulses
from the sense organs
or receptors to the
spinal cord and brain

Question 2

motor neuron

Answer 2

Transmits impulses
from the brain and
spinal cord to the
effectors (muscles and
glands). The effectors
bring about the
response.

Question 3

what is the function of the myelin sheath

Answer 3

the sheath insulates the axon so that it transmits impulses faster.

Question 4

what is a reflex arc

Answer 4

The reflex arc is the path along which an impulse is transmitted to bring
about a response to a stimulus during a reflex action

Question 5

what is the significance of a simple reflex arc

Answer 5

they are inborn safety mechanism to protect the body by producing immediate responses to changes in the external and internal enviroment

Question 6

significance of synapses

Answer 6

• allows a signal to pass from one neuron to another.
• gap between axon of one neuron and the dendrite of another.
• an electrical impulse travels along an axon but cannot move across the gap between cells
• this impulses cause the nerve ending of a neuron to release molecules called neurotransmitters
• these neurotransmitters move across the synaptic gap and bind to receptor molecules on the cell membrane of the next neuron.
• this stimulates the second neuron to transmit the electrical impulse.