Nervous System

Question 1

Neuron is made up of three basic parts

Answer 1

• Cell Body
• Dendrite
• Axon

Question 2

The Neuron

Answer 2

is the structural unit or building block of the nervous

system

Question 3

Cell body

Answer 3

The neuron cell body contain the organelles that are

common to all cells: a cell membrane, nucleus, endoplasmic reticulum, and cytoplasm

Question 4

Dendrites

Answer 4

a short branched extension of a neuron, along which

impulses received from other cells at synapses are transmitted to the cell body.

Question 5

Axon

Answer 5

a long, thin process extending from the cell body. The axon’s cell membrane incorporates specialized protein ion channels that enable the axon to conduct an electrochemical signal (action potential) from the cell body to the axon terminals. Axon terminals of one neuron make synaptic contacts with other neurons’ dendrites or
on the cell body itself

Question 6

Synapse

Answer 6

When the action potential reaches the axon terminals, a
neurotransmitter is released from synaptic vesicles into the terminals. The neurotransmitter molecules act on receptor molecules that are part of ion channels in the dendrites and soma of the next neuron in a chain.

Question 7

A typical chemical synapse consists of

Answer 7

a terminal bouton (a swelling at the end of an axon terminal) that includes a presynaptic membrane, a
specialized postsynaptic membrane, and a space between the two (the synaptic cleft). The terminal bouton contains many synaptic vesicles that contain neurotransmitter molecules.

Question 8

presynaptic and postsynaptic regions contain

Answer 8

numerous mitochondria, which supply the energy needed by the synaptic transmission process

Question 9

Types of Neurons:

Answer 9

1) Unipolar
2) Bipolar
3) Multipolar
4) Special types: Purkinje, Stellate, Pyrimidal

Question 10

Special Histological Stains for Nerve Tissue

Answer 10

• Golgi preparations: Great for isolating individual neurons for viewing.
• Nissl preparations: Great for demonstrating cell bodies of neurons.
• Myelin preparations: Stain myelinated fibers and not the cell bodies or dendrites.
• H&E preparations (Haematoxylin & Eosin): usually used for normal nerve tissue staining.

Question 11

central nervous system (CNS)

Answer 11

the brain and spinal cord

Question 12

peripheral nervous system (PNS)

Answer 12

nerves and ganglia

Question 13

Collections of axons that carry action potentials from one place to another are called in the PNS are called

Answer 13

nerves

Question 14

Collections of axons that carry action potentials from one place to another are called in the CNS

Answer 14

tracts

Question 15

Clusters of neuron cell bodies in the PNS are called

Answer 15

ganglia

Question 16

Clusters of neuron cell bodies in the CNS are called

Answer 16

nuclei or cortices

Question 17

Glial Cells:

Answer 17

Non-neural cells that provide a variety of support functions for the neurons that relate to nutrition, regulation of the extracellular environment
including the blood-brain barrier, immune system, myelin insulation for many axons, and a host of other support function

Question 18

Astrocytes

Answer 18

found throughout the CNS

Question 19

Astrocytes regulate

Answer 19

the ionic composition and pH of the extracellular environment and secrete various neuroactive
substances.

Question 20

Astrocyte end-feet form the

Answer 20

glia limitans, a coating of the inner surface of the pia mater that surrounds the brain and spinal cord

Question 21

Glial Cells: 6 Types:

Answer 21

• 1) Microglia
• 2) Astrocytes
• 3) Satellite
• 4) Ependymal
• 5) Oligodendrocytes
• 6) Schwann Cells

Question 22

Microglia

Answer 22

clean up cellular debris via phagocytosis

Question 23

Astrocytes

Answer 23

support and repair neurons; form the brain-blood barrier within the CNS

Question 24

Satellite

Answer 24

form the brain-blood barrier within the CNS, function similarly to astrocytes

Question 25

Ependymal

Answer 25

form epithelial lining of the CNS & produce cerebrospinal fluid

Question 26

Oligodendrocytes

Answer 26

myelinates axons of the neurons in the CNS

Question 27

Schwann Cells

Answer 27

myelinates axons of the neurons in the PNS

Question 28

Meninges:

Answer 28

Covering of the CNS

Question 29

Dura Mater

Answer 29

The tough outermost lining covering the brain and spinal cord.

Question 30

Arachnoid Mater

Answer 30

A delicate fibrous membrane forming the middle of the three coverings of the central nervous system. The arachnoid mater is named for the delicate, spider-web-like filaments that extend from its deep surface, through the cerebrospinal fluid of the subarachnoid space, to the pia mater.

Question 31

Pia Mater

Answer 31

the delicate innermost layer of the meninges, the | membrane surrounding the brain and spinal cord.

Question 32

Forebrain:

Answer 32

the anterior part of the brain, including the cerebral hemispheres, the thalamus, and the hypothalamus. Also called proencephalon.

Question 33

Hindbrain:

Answer 33

the lower part of the brainstem, comprising the | cerebellum, pons, and medulla oblongata. Also called rhombencephalon.

Question 34

The CNS has two kinds of tissue:

Answer 34

grey matter and white matter

Question 35

Grey matter

Answer 35

which has a pinkish-grey color in the living brain, contains the cell bodies, dendrites and axon terminals of neurons, so it is where all synapses are.

Question 36

White matter

Answer 36

is made of axons connecting different parts of grey matter to each other. Unlike the white matter, the neurons of grey matter do not have extended axons

Question 37

Grey matter

Answer 37

no myelin sheath

Question 38

white matter

Answer 38

is myelinated

Question 39

node of Ranvier

Answer 39

carry out the complicated exchange of sodium | and potassium ions across the membrane that is the basis of the conduction of the action potential.

Question 40

spinal cord extends from

Answer 40

medulla to space between L1 and L2 | vertebrae

Question 41

A bundle of neurons surrounded by connective tissue is called a

Answer 41

Fascicle

Question 42

A bundle of Fasicles surrounded by connective tissue is called a

Answer 42

Nerve

Question 43

Peripheral nerve fibers carry

Answer 43

motor, sensory, and autonomic nerve | fibers

Question 44

The posterior root contains only

Answer 44

sensory neurons

Question 45

anterior root contains

Answer 45

motor neurons and fibers from the | autonomic nervous system

Question 46

Spinal nerves originate from the

Answer 46

Spinal Cord at a junction of an anterior and posterior root extending from the spinal cord.

Question 47

The posterior root carries

Answer 47

sensory neurons from the body back to the | CNS.

Question 48

The anterior root carries

Answer 48

motor neurons from the CNS to the muscles | and internal organs

Question 49

Dermatome

Answer 49

An area of the skin supplied by | nerves from a single spinal root

Question 50

The Autonomic Nervous System composed of three divisions:

Answer 50

sympathetic, parasympathetic, and enteric.

Question 51

The enteric division consists of

Answer 51

a vast number of neurons arranged in a network of plexuses in the walls of the gut.