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Question 1

what is a stimuli

Answer 1

a thing/event that evokes a functional reaction

Question 2

what are sensory receptors

Answer 2

a group of cells that can detect a change in the environment

Question 3

how does the nervous system coordinate a response

Answer 3

when receptors detect a stimulus its converted into an electrical impulse and sent to the sensory neuron. The CNS responds to the stimulus and the impulses travel along the relay neuron. The CNS sends info to the effector along a motor neuron and the muscle may contract or the gland may secrete a hormone

Question 4

what is reaction time

Answer 4

the time it takes to respond to a stimulus

Question 5

how do neurons speed up impulse

Answer 5

neurons are long which speeds up the impulse as connecting with many smaller neurons is time-consuming so one long one is faster.

Question 6

what do dendrites/dendrons and axons do

Answer 6

dendrites and dendrons carry nerve impulses to the cell body and axons carry impulses away from the cell body

Question 7

what are axons surrounded by

Answer 7

the myelin sheath that acts as an electrical insulator, speeding up the electrical impulse

Question 8

what is the structure of the sensory neurone

Answer 8

one long dendron carries impulses to the cell body which is in the middle of the Neurone.One short axon carries nerve impulses away from the cell body to the CNS

Question 9

what is the structure of the motor neurone

Answer 9

many short dendrites carry nerve impulses from the CNS to the cell body.One long axon carries impulses from the cell body to the effector cells

Question 10

what is the structure of the relay neurone

Answer 10

many short dendrites carry nerve impulses from the sensory neurones to the cell body.An axon carries nerve impulses from the cell body to motor neurones