nervous system

Question 1

Where do electrical impulses travel?

Answer 1

CNS and PNS

Question 2

What is the CNS composed of?

Answer 2

brain and spinal cord

Question 3

What is the PNS composed of?

Answer 3

all peripheral nerves extending throughout the body (except brain and spinal cord)

Question 4

What is an axon?

Answer 4

an extension of the neuron

Question 5

axon function?

Answer 5

electrical insulator

Question 6

what covers the axon?

Answer 6

myelin sheath

Question 7

What is a myelin sheath?

Answer 7

insulating layer that forms around the nerve

Question 8

what forms a myelin sheath?

Answer 8

cell membrane of Schwann cell

Question 9

what type of cell is a Schwann cell?

Answer 9

glia cell

Question 10

where are Schwann cells located?

Answer 10

on neuron of peripheral division

Question 11

What cell enables electrical impulses to travel faster?

Answer 11

Schwann cell

Question 12

Are Schwann cells in the CNS or PNS?

Answer 12

PNS

Question 13

do glia cells carry electrical impulses?

Answer 13

no

Question 14

What is a node of Ranvier?

Answer 14

a gap between each Schwann cell

Question 15

What does a dendrite do?

Answer 15

receive impulses from another neuron or sensory receptor

Question 16

How does the brain receive impulse?

Answer 16

• dendrite receives impulse
• impulse travels from dendrite to axon
• impulse reaches terminal knob at the end of the axon
• impulse then travels from neuron to neuron until it reaches the brain

Question 17

What are the 2 types of impulses?

Answer 17

1. sensory

2. motor

Question 18

sensory impulse

Answer 18

travel from receptor to brain

Question 19

sensory neurons

Answer 19

neuron that carry sensory impulses

Question 20

motor impulse

Answer 20

travel from brain to effector (muscles and glands)

Question 21

motor neurons

Answer 21

neurone that carry motor impulses

Question 22

glia cells

Answer 22

support cells in the nervous system

Question 23

resting neuron

Answer 23

a neuron that is not conducting an impulse

Question 24

what is resting potential?

Answer 24

the electrical charge across the cell membrane of a neuron in its resting state

Question 25

what does a resting neuron pump in and out

Answer 25

- sodium out | - potassium in

Question 26

what is an action potential?

Answer 26

when the dendrite receives a signal from the sensory receptor

Question 27

what is the process of action potential?

Answer 27

- sodium ions from outside the cell rush in and potassium rush out - this temporarily reverses the polarity and the outside is more negative - this sudden exchange produces the nerve impulse - the region of reversed polarity moves like a wave along the neuron - this region is called the action potential - ions return to their resting potential after the action passes

Question 28

synapse

Answer 28

a gap between each cell

Question 29

what is a neurotransmitter?

Answer 29

a molecule secreted by neuron or glial cell to affect another cell across the synapse

Question 30

what does a nucleoli do?

Answer 30

make ribosomes for protein synthesis

Question 31

what are Nissl bodies?

Answer 31

clumps of rough er

Question 32

4 types of neurons

Answer 32

1. unipolar 2. bipolar 3. pseudo unipolar 4. multipolar

Question 33

are motor neurons long or short?

Answer 33

long

Question 34

grey matter?

Answer 34

non myelinated axons

Question 35

white matter?

Answer 35

myelinated axons

Question 36

do myelinated or unmyelinated axons conduct impulses faster?

Answer 36

myelinated

Question 37

what do microglial cells do?

Answer 37

get rid of bad stuff

Question 38

what do olgiodendrocytes do?

Answer 38

make myelin sheath

Question 39

what is an astrocyte?

Answer 39

satellite cell

Question 40

what does an astrocyte do?

Answer 40

- support neuron | - hugs capillary

Question 41

what does a ependymal cell do?

Answer 41

create CSF

Question 42

6 types of neuroglia

Answer 42

1. ependymal cells 2. astrocytes 3. microglia 4. oligodendrocytes 5. satellite cells 6. Schwann cell

Question 43

what do afferent nerves do?

Answer 43

conduct impulse towards the CNS

Question 44

what do efferent nerves do?

Answer 44

conduct impulse away from CNS

Question 45

what does a sodium potassium pump use?

Answer 45

ATP

Question 46

depolarization

Answer 46

inside of cell quickly becomes positively charged

Question 47

what opens during depolarization?

Answer 47

sodium channels

Question 48

what closes during repolarization?

Answer 48

sodium | - potassium open and rush out

Question 49

what has to be met for action potential to happen?

Answer 49

threshold

Question 50

saltatory conduction

Answer 50

jumping from node to node

Question 51

acetylcholinesterase

Answer 51

enzyme that causes rapid hydrolysis of acetylcholine