Nervous System

Question 1

Ependymal cells

Answer 1

promote circulation of the cebrospinal fluid, associated with the CNS

Question 2

Astrocytes

Answer 2

facilitate information transfer, regulate extracellular ion concentrations, promote blood flow to neurons, help form the blood- brain barrier, act as stem cells to replenish certain neurons in the CNS

Question 3

Oligodendrocytes

Answer 3

Myelinate axons in the CNS. Myelination increases the conduction speed of action potentials.

Question 4

Microglia

Answer 4

function in the CNS, protect against pathogens

Question 5

Schwann cells

Answer 5

myelinate axons in the PNS

Question 6

CNS

Answer 6

Brain and Spinal cord

Question 7

Explain the system between the brain and spinal cord

Answer 7

The spinal cord conveys information to and from the brain and generates basic patterns of locomotion.

Question 8

How are reflexes mediated?

Answer 8

By the spinal cord or lower brain

Question 9

PNS

Answer 9

cranial nerves, ganglia, and spinal nerves

Question 10

white matter

Answer 10

consists of bundled axons

Question 11

gray matter

Answer 11

neuron cell bodies

Question 12

Motor system

Answer 12

peripheral nervous system composed of motor neurons carry signals to skeletal muscles

Question 13

Autonomic nervous system

Answer 13

involuntary system that regulates the internal environment and consists of the sympathetic and parasympathetic divisions of the autonomic nervous system regulate organs of the cardiovascular, excretory, and endocrine systems.

Question 14

sympathetic division

Answer 14

responsible for the “fight or flight” response. In mammals, the heart beats faster, digestion slows or stops, and the adrenal medulla secretes more epinephrine (adrenaline)

Question 15

Identify the ions involved in membrane potentials

Answer 15

Potassium (K+) and Sodium (Na+)

Question 16

The concentration of K+ is _____ (higher/lower) in the cell, while the concentration of Na+ is _____ (higher/lower) outside

Answer 16

higher, higher

Question 17

equilibrium potential

Answer 17

the membrane potential at which there is no net movement of the ion across the membrane.

Question 18

when is there no net flow of ions across the membrane

Answer 18

If the membrane potential equals the equilibrium potential for a particular ion (AT REST)

Question 19

Potassium in membrane potential

Answer 19

Higher concentration inside compared to out. when K+ is at rest, the membrane is more permeable to potassium than sodium, resulting in a greater EXIT flow of K+ ions, contributing to the resting membrane potential

Question 20

Sodium in membrane potential

Answer 20

Higher concentration outside compared to inside. The neuron’s membrane at rest is more permeable to potassium than sodium so the entry of sodium is limited.

Question 21

Sodium ions equilibrium potentials (ENA+EK)

Answer 21

the EQ is positive due to the higher concentration of Na+ outside of the neuron compared to inside

Question 22

Potassium ions in equilibrium potentials (ENA + EK)

Answer 22

EQ is negative due to the higher concentration of K+ inside the neuron compared to out

Question 23

Leakage channels

Answer 23

Non gated channels that allow the passive movements of ions across the membrane at all times

Question 24

Resting potential

Answer 24

resting neuron not sending a signal, resting potential is around -60 to -80 mV

Question 25

Graded Potential

Answer 25

Changes in membrane potential that vary in size. Can be either depolarized or hyperpolarized.

Question 26

Hyperpolarization

Answer 26

Undershot, way below threshold

Question 27

Depolarization

Answer 27

sodium channels open

Question 28

Repolarization

Answer 28

Na+ channels inactive, K+ channels close

Question 29

Action Potential (membrane potential)

Answer 29

triggered when membrane potential reaches a certain threshold, around –55 mV

Question 30

Ligand gated ion channels STEP 1

Answer 30

Action potential reaches, + presynaptic membrane depolarizes

Question 31

Ligand gated ion channels STEP 2

Answer 31

Voltage gated CA2+ channels open and CA2+ concentration increased

Question 32

Ligand gated ion channels STEP 3

Answer 32

Synaptic vesicles fuse w/ presynaptic vesicles

Question 33

Ligand gated ion channels STEP 4

Answer 33

Neurotransmitters bind ligand- gated channels, allowing Na+ and K+ to diffuse through

Question 34

Spatial summation

Answer 34

Stimuli is applied at the same time but in different areas

Question 35

Temporal summation

Answer 35

one presynaptic neuron releases neurotransmitters many times over a period of time

Question 36

Inhibitory postsynaptic potential

Answer 36

Hyperpolarization in the membrane caused by the binding of an inhibitory neurotransmitter from a presynaptic cell to a postsynaptic receptor; this makes it more difficult for a postsynaptic neuron to generate an action potential

Question 37

Excitatory postsynaptic potential

Answer 37

Depolarization in the membrane caused by the binding of an excitatory neurotransmitter from a presynaptic cell to a postsynaptic receptor.

Question 38

Cerebrum

Answer 38

controls skeletal muscle contraction. The center for learning, emotion, memory and perception

Question 39

Cerebellum

Answer 39

coordinates movement and balance and helps in learning and remembering motor skills

Question 40

midbrain

Answer 40

receives and integrates sensory information and sends it to the forebrain

Question 41

pons & medulla

Answer 41

transfer information between the PNS and the midbrain and forebrain and coordinate large scale body movements (ex.running)