module 2

Question 1

extensions that branch out from the cell body to receive info from other neurons

Answer 1

dendrite

Question 2

extends like tail from the soma and carries info away

Answer 2

axon

Question 3

what is the largest organelle in a neuron

Answer 3

nucleus

Question 4

branches at the end of the axon that contain neurotransmitters

Answer 4

axon terminal

Question 5

chemicals released by the neuron to communicate with muscle, organs or another neuron

Answer 5

neurotransmitter

Question 6

what is the largest part of a neuron?

can you see a neuron with your naked eye

Answer 6

cell body

nope

Question 7

The connection between 2 neurons is called a ______

Answer 7

synapse

Question 8

The transmitting neuron is called the ____ and the receiving neuron is called the _______

Answer 8

presynaptic neuron

postsynaptic neuron

Question 9

what are the stages of the action potential

Answer 9

1. resting
2. threshold
3. depolarization
4. repolarization
5. absolute and relative refractory period

Question 10

where do action potentials occur

Answer 10

nodes of ranvier

Question 11

what happens at resting potential

what is the voltage

Answer 11

Na/K pumps are closed

-70 mV

Question 12

sodium concentrations are ___ outside of cell and potassium concentration are ____ outside of the cell at resting potential

Answer 12

high

low

Question 13

where does the threshold charge come from

what is the threshold charge

Answer 13

local potential

-55 mV

Question 14

what causes depolarization

what is the charge

Answer 14

influx of sodium ions into the cell

+40 mV

Question 15

what happens during repolarization
what happens to the charge
what is the charge

Answer 15

sodium gates close and potassium gates open and leave the cell
it overshoots resting potential
-80 mV

Question 16

what is the relative refractory period

Answer 16

time when another action potential can be generated but only by a stronger than threshold stimulus

Question 17

what is the absolute refractory period

Answer 17

when the sodium ion channels are open but unable to respond the any further stimulation

Question 18

what allows the relative refractory period to happen

Answer 18

closed sodium channels and open potassium channels

Question 19

what four factors affect membrane potential

Answer 19

semi-permeable
electrostatic pressure
sodium-potassium pump
difussion

Question 20

how does the neuron’s semi-permeable membrane affect membrane potential

Answer 20

it contributes to polarization which meaning there is a difference in charge inside and outside of the cell

Question 21

how does the neuron’s electrostatic pressure affect membrane potential

Answer 21

it causes ions to repel from the side that is similarly charged and attraction to the side that is oppositely charged which balances ions

Question 22

how does the neuron’s diffusion affect membrane potential

Answer 22

cause ions to move to the areas where they are less concentrated

Question 23

how does the neuron’s sodium-potassium pump affect membrane potential

Answer 23

it keeps the inside of the membrane to be more negative compared to outside

Question 24

_____ sodium ions are moved out for every ____ potassium ions

Answer 24

three

two

Question 25

partial depolarization of dendrites and cell body

Answer 25

excitatory postsynaptic potential

Question 26

hyperpolarization of the dendrites and cell body

Answer 26

inhibitory postsynaptic potential

Question 27

form the ion channel and open quickly to produce immediate reactions required for muscle activity and sensory processing

Answer 27

ionotropic receptors

Question 28

opens channels indirectly through a second messenger and acts slowly to produce longer-lasting effects

Answer 28

metabotropic receptors

Question 29

nonneural cells that hold neurons together, increase the speed of conduction and produce myelin

Answer 29

glial cells

Question 30

which types of glial cells actually produce myelin and where are they located

Answer 30

oligodendrocytes in the brain and spinal cord | Schwann cells in the nervous system

Question 31

fatty tissue that wraps around the axon to insulate it from surrounding fluid and other neurons

Answer 31

myelin

Question 32

how does myelin affect neurosignalling

Answer 32

reduces capacitance | speeds up graded potential

Question 33

what are the 3 methods for cleaning up the synapse

Answer 33

inactivation reuptake destroyed by astrocytes

Question 34

where are large and small neurotransmitters packaged

Answer 34

small ones are packaged in the synaptic terminals | large ones are in vesicles