nervous system

Question 1

what are the 2 main divisions of the nervous system?

Answer 1

CNS- central nervous system
PNS - peripheral nervous system

Question 2

what 2 structures make up the central nervous system

Answer 2

1. brain
2. spinal cord

Question 3

what is the order of events from stimulus to response?

Answer 3

stimulus –> receptors –>neural network/brain –> effectors(motor nerves) –> response

Question 4

What are afferent nerves

Answer 4

sensory nerves that bring information into the central nervous system

Question 5

what are efferent nerves

Answer 5

motor nerves that deliver information from the CNS to the PNS

Question 6

what type of signals do neurons transmit

Answer 6

chemical and electrical signals

Question 7

what is a dendrite?

Answer 7

branches at the start of the nerve that receive and send messages to travel along the cell body

Question 8

what is an axon?

Answer 8

long extension of a neuron that carries nerve impulses AWAY from the cell body

Question 9

what is the function of the myelin sheath?

Answer 9

speed up the action potential(signal)

Question 10

what is the space between 2 neurons

Answer 10

a synapse

Question 11

what are the 3 types of neurons?

Answer 11

motor, sensory, interneurons

Question 12

what is the threshold of excitation?

Answer 12

strength of a stimulus needed to induce an action potential

Question 13

what is reuptake

Answer 13

the reabsoprtion of neurotransmitterby a presynaptic neuron after it has performed its function of transmitting a neural impulse

Question 14

what is postsynaptic

Answer 14

term to describe the cell that is receiving the neurotransmitter during synaptic transmission

Question 15

presynaptic neuron

Answer 15

the neuron that is releasing the neurotransmitter

Question 16

what is repolarization

Answer 16

after sodium ions have rushed into the cell, potassium ions rush out of the cell to restore the balance and the original polarity

Question 17

what are neurotransmitters

Answer 17

chemical messengers that cross the synaptic gaps between neurons

Question 18

what is a neuron?

Answer 18

a nerve cell that is specialized to receive and conduct electrical impulses

Question 19

what is saltatory conduction?

Answer 19

the rapid skipping of an action potential from node to node on myelinated neurons

Question 20

threshold stimulus

Answer 20

the minimal level of stimulation required to cause an action potential

Question 21

what is the impulse that travels between neurons?

Answer 21

chemical impulse

Question 22

what is the impulse that travels across neurons?

Answer 22

electrical current

Question 23

subthreshold stimulus

Answer 23

a stimulus too small to create an action potential in a neuron

Question 24

what is depolarization

Answer 24

the process during the action potential when sodium is rushing into the cell causing the interior to become more positive

Question 25

what is an action potential?

Answer 25

the movement of ions across a neuron’s membrane. also known as an impulse