Physiology: The Nervous System

Question 1

Central Nervous System (CNS) is made up of (structurally):

Answer 1

▪brain

▪spinal cord

Question 2

Peripheral Nervous System (PNS) made up of:

Answer 2

▪cranial nerves and their branches
▪spinal nerves and their branches
▪ganglia
▪enteric plexuses
▪sensory receptors

Question 3

what is a nucleus/nuclei:

Answer 3

-cluster of neuronal cell bodies in the CNS

Question 4

what are ganglion/ganglia?

Answer 4

-cluster of neuronal cell bodies in the PNS

Question 5

what is a tract?

Answer 5

-bundle of axons in the CNS

Question 6

what is a nerve?

Answer 6

-bundle of axons in the PNS

Question 7

what is grey matter composed of?

Answer 7

collections of cell bodies and UNmyelinated nerve fibres in the CNS

Question 8

what is white matter composed of?

Answer 8

myelinated axons in the CNS

Question 9

what does the spinal cord taper into at L2?

Answer 9

conus medullaris

Question 10

what are the roots of the spinal nerves?

Answer 10

cauda equinas

Question 11

Functions of the NS:

Answer 11

1) Sensory
▪detection and input
2) Integrative
▪processing/storing/analyzing of sensory info
▪decision-making
3) Motor
▪output

Question 12

what are the two type of nervous cells?

Answer 12

1) Neurons

2) Neuroglia

Question 13

Role of neuroglia?

Answer 13

▪support neurons
▪nourish “ “
▪protect “ “

Question 14

what are the parts of a neuron?

Answer 14

dendrite, cell body, axon

Question 15

function of a dendrite?

Answer 15

it is the input portion of the neuron

Question 16

function of cell body AKA soma?

Answer 16

cell processes (e.g. protein synthesis)

Question 17

the end of an axon divides into many fine processes called:

Answer 17

axon terminals

Question 18

the swollen ends of some axon terminals:

Answer 18

synaptic bulb

Question 19

a multilayered lipid and protein covering that speeds up signal (‘action potential’) conduction:

Answer 19

myelin

Question 20

an electrical signal that travels along the cell membrane of a neuron:

Answer 20

action potential

Question 21

Structural Classification of Neurons (3 of them) and why:

Answer 21

1) multipolar
2) bipolar
3) unipolar

of process extending from the cell body

Question 22

all motor neurons are (structure):

Answer 22

multipolar

Question 23

most neurons in the brain and spinal cord (structure):

Answer 23

multipolar

Question 24

sensory neurons in the PNS are (structure):

Answer 24

unipolar

Question 25

Functional Classification of Neurons-how classified and what types (3)?:

Answer 25

functionally, they are classified according to the direction in which the AP is conducted with respect to the CNS 1) sensory neurons 2) motor neurons 3) interneurons

Question 26

Sensory Neurons a.k.a. (directional):

Answer 26

afferent neurons

Question 27

Motor Neurons AKA (directional):

Answer 27

efferent neurons

Question 28

Interneurons a.k.a.

Answer 28

association neurons

Question 29

most interneurons are ______ polar

Answer 29

multi

Question 30

the site of communication between two neurons or between a neuron and another type of cell:

Answer 30

synapse

Question 31

2 types of synapses:

Answer 31

electrical and chemical

Question 32

Electrical Synapses: APs conduct directly between the plasma membranes of adjacent cells through ______________________

Answer 32

gap junctions

Question 33

the space between the communicating neurons _________________

Answer 33

synaptic cleft

Question 34

chemical synapses are _________ (than electrical)

Answer 34

slower

Question 35

Neuroglia of the CNS (4 types):

Answer 35

1) astrocytes 2) oligodendrocytes 3) microglia 4) ependymal cells

Question 36

2 roles of astrocytes:

Answer 36

▪help form the blood-brain barrier (BBB) | ▪provide nutrients to neurons

Question 37

role of oligodendrocytes:

Answer 37

form/maintain the myelin sheath of CNS neurons

Question 38

where are epydymal cells in the body?

Answer 38

they line the cavities of the brain and spinal cord

Question 39

The neuroglia of the PNS are _________ cells:

Answer 39

Schwann

Question 40

what cells form the myelin sheath of PNS axons?

Answer 40

Schwann cells

Question 41

where does the spinal cord end, inferiorly?

Answer 41

L2

Question 42

a small tube in the centre of the SC that contains CSF is the _______________

Answer 42

central canal

Question 43

the horns of the grey matter of the spinal cord are called the:

Answer 43

- posterior (a.k.a. dorsal) horn | - anterior (a.k.a. ventral) horn

Question 44

in white matter of spinal cord, _____ (a.k.a. _________) tracts consist of axons that conduct APs away from the brain

Answer 44

motor; descending

Question 45

in white matter of spinal cord, _____ (a.k.a. _________) tracts consist of axons that conduct APs away from the brain

Answer 45

sensory; ascending

Question 46

Brain Structure, 4 parts:

Answer 46

1) brain stem 2) cerebellum 3) diencephalon 4) cerebrum

Question 47

3 regions of the brain stem:

Answer 47

3 regions: medulla oblongata, pons, midbrain

Question 48

continuous with the SC, it is the part between the SC and the diencephalon:

Answer 48

brain stem

Question 49

In brain: contains centres (nuclei) for the control of heart rate, blood pressure, breathing, swallowing, and vomiting

Answer 49

medulla oblongata

Question 50

contains centres for the control of breathing

Answer 50

pons

Question 51

contains centres for reflex visual activities (e.g. tracking moving objects, scanning stationary objects), hearing

Answer 51

midbrain

Question 52

- a net-like formation of neural tissue that spreads throughout the brain stem - contains the (RAS)

Answer 52

reticular formation

Question 53

where is the reticular formation located?

Answer 53

brain stem

Question 54

▪smoothes and coordinates skeletal muscle contraction | ▪regulates posture and balance

Answer 54

cerebellum

Question 55

Diencephalon includes 3 parts:

Answer 55

:a) hypothalamus b) thalamus c) epithalamus

Question 56

what part of brain responsible for: ▪major regulator of homeostasis ▪controls and integrates the autonomic nervous system ▪hormone production ▪emotion and behaviour (with the limbic system) ▪eating, drinking ▪body temperature ▪circadian rhythm (a 24 hour cycle in the biochemical, physiological and/or behavioural processes of living things)

Answer 56

hypothalamus

Question 57

what part of the brain is the major relay station for most sensory input to the cerebral cortex?

Answer 57

thalamus

Question 58

what area of the brain contains the pineal gland and is involved in smelling (especially emotional responses to smells)?

Answer 58

epithalamus

Question 59

which part of brain consists of: ▪an outer rim of grey matter (cerebral cortex); ▪an inner region of white matter(association areas); and ▪grey matter nuclei deep within the white (basal ganglia)

Answer 59

cerebrum

Question 60

In brain: ▪contains sensory areas involved in perception ▪contains motor areas involved in the execution of voluntary movements

Answer 60

cerebral cortex

Question 61

In brain are that: •helps to regulate the starting and stopping of movements •helps control subconscious contraction of skeletal muscles •helps suppress unwanted movement •helps to set resting muscle tone

Answer 61

basal ganglia AKA basal nuclei

Question 62

three protective layers of CT encircle the brain and SC, what are they called as a unit?

Answer 62

meninges

Question 63

what are the 3 layers of meninges?

Answer 63

1) dura mater –tough outer layer 2) arachnoid membrane –middle layer 3) pia mater –inner layer

Question 64

in the PNS: damage to ________ and myelinated axons can be repaired if the cell body is intact and ________cells are active

Answer 64

dendrites; Schwann

Question 65

can damaged neurons be repaired in the CNS?

Answer 65

mostly no