Chapter 4: The Nervous System

Question 1

Neurons are specialized cells capable of

Answer 1

Transmitting electrical impulses and then translating those electrical impulses into chemical signal

Question 2

Where is the nucleus located in the neuron

Answer 2

Cell body (soma)

Question 3

Soma is also the location of

Answer 3

Endoplasmic reticulum and ribosomes

Question 4

Dendrites receive

Answer 4

Incoming messages from other cells

Question 5

Information received from the dendrites is transmitted

Answer 5

Through the cell body before it reaches the axon hillock

Question 6

Axon hillock integrates the

Answer 6

Incoming signals

Question 7

Axon hillock plays an Important role in

Answer 7

Action potentials

Question 8

Action potentials is the transmission of

Answer 8

Electrical impulses down the axon

Question 9

Signals arriving from the dendrites can be either

Answer 9

Excitatory or inhibitory

Question 10

Axon is a long appendage that

Answer 10

Terminates in close proximity to a target structure

Question 11

Axon carry neural signals

Answer 11

Away from the soma

Question 12

Dendrites carry signals

Answer 12

Toward the soma

Question 13

Myelin is a fatty membrane that

Answer 13

Prevents signal loss or crossing of signals

Question 14

Myelin sheath maintains the

Answer 14

Electrical signal within one neuron

Question 15

Myelin increases the

Answer 15

Speed of conduction in the axon

Question 16

Myelin is produced by

Answer 16

Oligodendrocytes and Schwann cells

Question 17

Oligodendrocytes are in the

Answer 17

Central nervous system

Question 18

Schwann cells are in the

Answer 18

Peripheral nervous system

Question 19

Nodes of Ranvier are

Answer 19

Small breaks in the myelin sheath with exposed areas of axon membrane

Question 20

Nodes of Ranvier are critical for

Answer 20

Rapid signal conduction

Question 21

What is at the end of an axon

Answer 21

Nerve terminal (synaptic bouton)

Question 22

The nerve terminal is enlarged and flattened to maximize

Answer 22

Transmission of the signal to the next neuron and ensure proper release of neurotransmitters

Question 23

Neurotransmitters are chemicals that

Answer 23

Transit information between neurons

Question 24

The synaptic cleft is

Answer 24

Space between neurons into which the terminal portion of the axon releases neurotransmitters

Question 25

Synaptic cleft bind to the

Answer 25

Dendrites of the adjacent neuron

Question 26

Synapse is

Answer 26

Nerve terminal, synaptic cleft, postsynaptic membrane

Question 27

Nerve is a bundle of

Answer 27

Neurons

Question 28

Nerves may be

Answer 28

Sensory, motor, mixed

Question 29

Cell bodies of neurons of the same type are clustered together into

Answer 29

Ganglia

Question 30

Axons may be bundled together to form

Answer 30

Tracts

Question 31

Cell bodies of neurons in the same tract are grouped into

Answer 31

Nuclei

Question 32

Astrocytes nourish

Answer 32

Neurons and form the blood brain barrier which controls the transmission of solutes from the bloodstream into nervous tissue

Question 33

Ependymal cells line the

Answer 33

Ventricles of the bran and produce cerebrospinal fluid

Question 34

Microglia are phagocytic cells that

Answer 34

Ingest and break down waste products and pathogens in the central nervous system

Question 35

Oligodendrocytes and Schwann cells produce

Answer 35

Myelin around axons

Question 36

Resting membrane potential is the

Answer 36

Net electric potential difference across the cell membrane

Question 37

Resting membrane potential is created by

Answer 37

Movement of charged molecules across that membrane

Question 38

Potassium leak channels allow the

Answer 38

Slow leak of K out of the cell

Question 39

Potential difference that represents this K+ equilibrium is called the

Answer 39

Equilibrium potential of K

Question 40

Pushing Na into the cell is facilitated by

Answer 40

Sodium leak channels

Question 41

Equilibrium potential of K is negative because

Answer 41

K+ is leaving the cell

Question 42

Equilibrium potential of Na+ is positive because

Answer 42

Sodium is moving into the cell

Question 43

Net effect of Na and K equilibrium potentials is called the

Answer 43

Resting membrane potential

Question 44

Na+/K+ ATPase continually pumps

Answer 44

Na and K back to where they started

Question 45

Excitatory input causes depolarization (raising the membrane potential, Vm, from its resting potential) and makes the

Answer 45

Neuron more likely to fire an action potential

Question 46

Inhibitory input causes hyperpolarization (lowering the membrane potential from its resting potential) and makes the

Answer 46

Neuron less likely to fire an action potential

Question 47

If the axon hillock receives enough excitatory input to be depolarized to the

Answer 47

Threshold value, an action potential is triggered

Question 48

Summation is the effect of

Answer 48

Multiple signals

Question 49

What are the two types of summation

Answer 49

Temporal and spatial

Question 50

Temporal summation is where multiple signals

Answer 50

Are Integrated during a short period of time

Question 51

Spatial summation is where the additive effects are based on

Answer 51

The number and location of the incoming signals

Question 52

Sodium channels can be closed meaning

Answer 52

Before the cell reaches threshold and after activation has been reversed

Question 53

Sodium channels can be open meaning

Answer 53

From threshold to about +35mV

Question 54

Sodium channels can be inactive meaning

Answer 54

From about +35mV to the resting potential

Question 55

Positive potential inside the cell triggers the voltage-gated sodium channels to inactivate and also triggers the

Answer 55

Voltage-gated potassium channels to open

Question 56

Repolarization is when the positively K cations are driven out of the cell and there will be

Answer 56

A restoration of the negative membrane potential

Question 57

During the absolute refractory period, no amount of stimulation can

Answer 57

Cause another action potential to occur

Question 58

During the relative refractory period, there must be a great than normal

Answer 58

Stimulation to cause an action potential

Question 59

Neurons starts at the resting potential which has a value of

Answer 59

-70mV

Question 60

At resting potential, what is K and Na like in and out of the cell

Answer 60

K is high inside the cell and low outside | Na is high outside the cell and low inside

Question 61

Impulse propagation is for when a signal has to be conveyed to another neuron and so the action potential has to travel

Answer 61

Down the axon and initiate neurotransmitter release

Question 62

Anesthetics work by blocking the

Answer 62

Voltage gated Na channels

Question 63

Increased length of the axon results in

Answer 63

Higher resistance and slow conduction

Question 64

Greater cross sectional areas allow for

Answer 64

Faster propagation due to decreased resistance

Question 65

Myelin is a good insulator which prevents

Answer 65

The dissipation of the electric signal

Question 66

Saltatory conduction is where the signal

Answer 66

Hops from node to node

Question 67

Neuron proceeding the synaptic cleft is the

Answer 67

Presynaptic neuron

Question 68

Neuron after the synaptic cleft

Answer 68

Postsynaptic cleft

Question 69

Neuron signals to a gland or muscle is called

Answer 69

Effector

Question 70

What allows a neurotransmitter to relay a message

Answer 70

Neurotransmitter molecule diffuse across the cleft and bind to receptors on the postsynaptic membrane

Question 71

Neurotransmitters can be broken down by

Answer 71

Enzymatic reaction

Question 72

Neurotransmitters can be brought back into the presynaptic neuron using

Answer 72

Reuptake carriers

Question 73

Neurotransmitters may simply diffuse out of the

Answer 73

Synaptic cleft

Question 74

What are some functions of the nervous system

Answer 74

Sensation and perception Motor function Memory Etc

Question 75

Afferent neurons ascend in the

Answer 75

Spinal cord toward the brain

Question 76

Efferent neurons exit the

Answer 76

Spinal cord on their way to the rest of the body

Question 77

Supraspinal circuits are used when

Answer 77

Some scenarios require input from the brain or brain stem

Question 78

White matter in the brain consists of

Answer 78

Axons encased in myelin sheaths

Question 79

Grey matter consists of

Answer 79

Unmyelinated cell bodies and dendrites

Question 80

Brain consists of what two matters

Answer 80

White and grey

Question 81

Spinal cord consists of what types of matter

Answer 81

Grey and white

Question 82

Axons of motor and sensory neurons are in the

Answer 82

Spinal cord

Question 83

Sensory neurons bring information in from the

Answer 83

Periphery and enter the dorsal side of the spinal cord (found in dorsal root ganglia)

Question 84

Motor neurons exit the spinal cord

Answer 84

Ventrally or side closest to the front of the body

Question 85

First neuron in the autonomic nervous system is called

Answer 85

Preganglionic neuron

Question 86

Second neuron in the autonomic nervous system is called

Answer 86

Postganglionic neuron

Question 87

What are the two types of reflex arcs

Answer 87

Monosynaptic and polysynaptic

Question 88

Monosynaptic reflex arc is where there is a signal synapse between

Answer 88

The sensory neuron that receives the stimulus and the motor neuron that responds to it

Question 89

Polysynaptic reflex arc is where there is at least one Inter neuron between the

Answer 89

Sensory and motor neurons