The Nervous system

Question 1

This part of the neuron receives info form other cells

Answer 1

Dendrites

Question 2

This part of the neuron holds all the normal cell components (nucleus, ribosomes, endoplasmic reticulum, etc.) and also is the main body of the cell

Answer 2

Soma

Question 3

This cell type isolates against signal loss on the axon, and is referred to as Schwann cells in the PNS and oligodendrocytes in the CNS

Answer 3

Myelin

Question 4

This part of the neuron integrates signals and starts signal transmission down the axon by summing up all the signals and seeing if they’re enough to cause an excitatory state

Answer 4

Axon hillock

Question 5

This part of the axon is formed from the breaks in myelin that allows for rapid signal transduction

Answer 5

Nodes of Ranvier

Question 6

This part of the neuron is located at the very end of the axon and releases neurotransmitters to their target

Answer 6

Nerve teminal

Question 7

The _____ includes the synaptic cleft, the axon terminal, and the post-synaptic membrane

Answer 7

Synapse

Question 8

What is the difference between nerves and tracts?

Answer 8

Nerves are many bundles of neurons in the PNS, and can be sensory, motor, or both

Tracts are made up of axon bundles in the CNS that cluster into nuclei and can only be made up of one type of cell per cluster (motor or sensory)

Question 9

These glial cells form the blood/brain barrier

Answer 9

Astrocytes

Question 10

These glial cells line the ventricles and produce cerebrospinal fluid

Answer 10

Ependymal cells

Question 11

These glial cells are phagocytic cells that ingest and break down waste

Answer 11

Micoglia

Question 12

_____ cells act as support for the neurons

Answer 12

Glial

Question 13

At rest, the neuron is more negative _____ than _____

Answer 13

Inside than outside

Question 14

Potassium is at a higher concentration ____ the cell than _____

Answer 14

Inside than outside

Question 15

Sodium is at a higher concentration _____ the cell than _____

Answer 15

Outside than inside

Question 16

Potassium leak channels allow potassium to flow _____ the cell while sodium leak channels allow sodium to flow ____ the cell

Answer 16

Out of

Into

Question 17

When the axon hillock receives an overall inhibitory signal, the cell ___ polarizes and is less likely to incur an action potential

Answer 17

Hyperpolarizes

inHibitory –> Hyperpolarizes

Question 18

When the axon hillock receives an overall excitatory signal, the cell ___ polarizes and is more likely to incur an action potential

Answer 18

Depolarizes

Excitatory –> dEpolarizes

Question 19

What is the difference between temporal and spatial summation?

Answer 19

Temporal summation occurs when multiple signals are integrated over a short period of time (based on time)

Spatial summation occurs when the additive affects are based on number and location of signals (based on position in space/location)

Question 20

Explain the entirety of action potential, from the beginning of stimulus to the return to resting potential

Answer 20

When the summation threshold is reached, sodium rushes into the cell until the cell reaches -50 mV. At +35 mV, at which point the action potential is reached, K+ channels open and allow K+ to leave the cell. This attempts to restore the resting potential, but overshoots it and causes hyperpoalization. This then results in a refractory period in which the cell cannot achieve another action potential as it returns to its resting potential

Question 21

What is the difference between absolute and relative refractory periods?

Answer 21

In absolute refractory periods, there is no amount of stimulation that can cause another AP to occur

In relative refractory periods, only greater than normal stimulation can cause an AP

Question 22

How do myelin and the nodes of Ranvier work together to allow for fast transmission of the AP?

Answer 22

The myelin insulates the axon, but the nodes of Ranvier are perfect for transmission. Bc of this, the AP jumps from node to node and this speeds it up

Question 23

This specific channel moves 2 K+ into the cell for every 3 Na+ ions and is responsible for restoring the resting potential of the cell

Answer 23

Na+/K+ ATPase