Neurons and Synaptic Transmission

Question 1

3 types of neuron

Answer 1

sensory, relay, motor

Question 2

contents of the soma

Answer 2

nucleus, including gnetic material of cell

Question 3

function of dendrites

Answer 3

carry nerve impulses to the cell body

Question 4

function of axon

Answer 4

carries nerve impulses away from cell body down length of neuron

Question 5

function of myelin sheath

Answer 5

protects axon and speeds up impulse transmission

Question 6

functions of sensory neuron

Answer 6

• carry nerve impulses from sensory receptors to spinal cord and brain
• convert information from sensory receptors into nerve impulses which are converted to information in the brain

Question 7

functions of relay neurons

Answer 7

• connect sensory neurons to motor neurons or to other relay neurons in the CNS
• allow neurons to communicate with each other

Question 8

what % of the CNS is relay neurons

Answer 8

97%

Question 9

length of axon and dendrites of relay neurons>

Answer 9

short axon
short dendrites

Question 10

length of axon and dendrites of sensory neurons

Answer 10

long axon
short dendrites

Question 11

length of axon and dendrites of motor neurons

Answer 11

long axon
long dendrites

Question 12

function of motor neurons

Answer 12

• connect CNS to muscles and glands
• cause muscles to allow movement

Question 13

function of the axon terminal?

Answer 13

allow neuron to communicate with the next neuron in the chain across the synapse

Question 14

fuction of the ode of ranvier

Answer 14

allow signals to jump across the between myelin

Question 15

normal charge inside nerve cell

Answer 15

-ve

Question 16

what happens when a neuron is activated?

Answer 16

inside of cell becomes +vely chanrged for a split second, causing an action potential to occur, creating an electrical impulse which moves down axon to the end of the neuron

Question 17

what does the electrical impulse do at the terminal buttons?

Answer 17

triggers the release of chemical neurotransmitters from synaptic vesicles in the terminal buttons, into the synapse

Question 18

what happens in the synapse

Answer 18

NTs bind to receptors on the surface of the post synaptic neuron and stiimulate it to generate its own electrical impulse

Question 19

summary of synaptic transmission (3)

Answer 19

1. action potential caused, creating an electrical impulse
2. impulse triggers release of NTs into synapse
3. NTs bind to receptors st8imulating an electrical impuls in next neuron