Chapter 9 Nervous Tissue

Question 1

What makes up the central nervous system (CNS)

Answer 1

brain and spinal cord

Question 2

What makes up the peripheral nervous system (PNS)

Answer 2

cranial nerves and spinal nerves

Question 3

what is the function of the central nervous system?

Answer 3

control center

Question 4

what does the peripheral nervous system do?

Answer 4

communicate between CNS and rest of body

Question 5

What is the division of the nervous system called where information comes in?

Answer 5

sensory

Question 6

what is the division of the nervous system called where information goes out?

Answer 6

motor nervous system

Question 7

What two types of cells make up nervous tissue?

Answer 7

neurons
neuroglia (glial)

Question 8

what do the neurons do?

Answer 8

transmit the action potential

Question 9

what do the neuroglia (glial) cells do?

Answer 9

support the neuron

Question 10

what is a nerve made up of?
many what?

Answer 10

neurons

Question 11

name the pink highlighted region

Answer 11

soma (cell body)

Question 12

name the pink highlighted region
what does it do?

Answer 12

dendrites
signals received from other sources

Question 13

name the pink highlighted region

Answer 13

axon

Question 14

in order, name the parts of the neuron where the action potential travels

Answer 14

dendrite to soma to axon

Question 15

name the pink highlighted region
what happens here?

Answer 15

axon terminals (synaptic knobs)
where cell communicates with other material

Question 16

name the pink highlighted region
what happens here?

Answer 16

axon hillock (trigger zone)
the action potential begins

Question 17

Where do the sensory (afferent) neurons carry information to?

Answer 17

into the brain or spinal cord

Question 18

where do motor (efferent) neurons carry information to?

Answer 18

out to muscles and glands

Question 19

Where are interneurons (association) located and where do they carry information to?

Answer 19

located in peripheral nervous system between sensory & motor pathways

Question 20

Which neuron makes up 90% of our neurons?

Answer 20

interneurons

Question 21

Are neuroglia (glial cells) electrically excitable?

Answer 21

no

Question 22

Do neurons or neuroglia multiply and divide by mitosis?

Answer 22

neuroglia

Question 23

Name the pink highlighted region (what kind of neuroglia is it?)
which nervous system?
what does it do?

Answer 23

oligodendrocyte
central
myelantes (wrap around) neurons

Question 24

name the pink highlighted section
what does it do?

Answer 24

microglial
phagocytes (macrophage) fights infection

Question 25

which neuroglia cells myelanate in the peripheral nervous system?

Answer 25

schwann cells

Question 26

what are the names for the two neurons involved in a synapse?

Answer 26

presynaptic neuron postsynaptic neuron

Question 27

what is a ligand-gated channel?

Answer 27

only opens when something binds to it

Question 28

what happens during depolarization in the cell?

Answer 28

the negative charge becomes less negative and becomes prepared for an action potential

Question 29

what happens during hyper polarization in the cell?

Answer 29

the negative charge is more negative than resting potential and is not ready to receive action potential stimuli

Question 30

What is a depolarizing postsynaptic graded potential called?

Answer 30

EPSP excitatory postsynaptic potential

Question 31

What is a hyperpolarizing postsynaptic graded potential called?

Answer 31

IPSP inhibitory postynaptic potential

Question 32

What is graded temporal summation?

Answer 32

multiple excitatory stimuli firing one right after the other that added together create enough charge for action potential

Question 33

what happens if i have an excitatory synapse and inhibatory synapse at the same time? what type of graded potential summation is this called?

Answer 33

they cancel out and never reach threshold for action potential spacial summation of IPSP and EPSP

Question 34

what is the action potential threshold charge for the action potential to take place?

Answer 34

-55

Question 35

what is the sequence of action potential?

Answer 35

* stimulus * threshold reached * action potential * depolarization (Na+ ions in) making positive charge in cell * repolarization (K+ ions out) * brief period of hyperpolarization

Question 36

what is hyperpolarization called after an action potential and why does it occur?

Answer 36

called relative refractory period to prevent action potential from going backwards

Question 37

Are sensory neurons called afferent or efferent?

Answer 37

afferent

Question 38

Are motor neurons called afferent or efferent?

Answer 38

efferent

Question 39

can each nerve contain sensory and motor neurons?

Answer 39

yes

Question 40

what happens if i have many excitatory synapses happening at at the same time all over from different nerves and the sum is enough for an action potential? what type of graded potential summation is this called?

Answer 40

spatial summation of stimuli

Question 41

what is no summation graded potential?

Answer 41

signals that fire but not in enough quantity or closely enough together to for an action potential