Ch. 1: Introduction To The Nervous System

Front 1

Two parts of the nervous system...

Back 1

Central (CNS)
Peripheral (PNS)

Front 2

CNS

Back 2

Central Nervous System
-ensconced in the skull and vertebral column
-includes BRAIN and SPINAL CORD

Front 3

PNS

Back 3

Peripheral Nervous System
-a collection of spinal (31 pairs) and cranial nerves (12 pairs)
-branches inflitrate virtually all parts of the body
-convey messages to and from CNS

Front 4

Optic Nerve

Back 4

an extension of the CNS, thus part of the CNS (not PNS)

Front 5

Olfactory nerve

Back 5

A collection of bipolar receptors neuron axons coming through the cribiform plate of the skull.
The olfactory bulb is CNS.

Front 6

Plexus

Back 6

network of nerves

Front 7

3 parts of the brain:

Back 7

-Cerebrum
-Cerebellum
-Brainstem

Front 8

Cerebrum (Forebrain)

Back 8

-2 cerebral hemispheres, divided by the logitudinal fissure
-diencephalon, hidden from view by cebral hemispheres

Front 9

Forebrain (prosencephalon) (2 parts)

Back 9

-Telecephalon (cerebral hemispheres)
-Diencephalon (thalamus plus...)

Front 10

Brain Stem (2 parts)

Back 10

-Midbrain (mesencephalon)
-Hindbrain (rhombencephalon)

Front 11

Hindbrain (2 parts)

Back 11

-Pons (metencephalon)
-Medulla oblongata (myelencephalon)

Front 12

Match:
-Brainstem
-Cerebellum
-Diencephalon
-Spinal Cord

Back 12

Front 13

Two types of nervous system cells:

Back 13

-Nerve cells (neurons)
-Glials cells

Front 14

Neurons

Back 14

information-processing and signaling elements
*around 100 billion in the nervous system

Front 15

Glial Cells

Back 15

play a variety of supporting roles
*May be more present than neurons (~10x more)

Front 16

Soma (perikaryon)

Back 16

Neroun cell body that supports the metabolic and synthetic needs of the rest of the neuron
(micrometers in size)

Front 17

Dendrites

Back 17

A series of branching, tapering processes that RECEIVE information from other neurons via SYNAPSES

Front 18

Axon

Back 18

one long, cylindrical process of a neuron that conducts information away from the cell body (SENDING)
-end in terminal branches that form synapses on other neurons
-have collaterals and diverging terminals
-can be a meter long

Front 19

Neurons are polarized...

Back 19

...with electrical signals traveling in only One Direction (haha) under ordinary physiological circumstances

Front 20

Neurons vary in...

Back 20

-Shape
-Size

Front 21

Multipolar

Back 21

there are multiple dendritic cells projections from the cell body and almost always an axon as well

Front 22

Bipolar

Back 22

2 processes

Front 23

Unipolar
Pseudounipolar (in vertebrates)

Back 23

Only one process

Front 24

Neuron classifications according to connections:

Back 24

-sensory neurons
-motor neurons
-interneurons
-projection neurons

Front 25

Sensory neurons

Back 25

either are directly sensitive to various stimuli (touch/temperature) or receive direct connections from nonneuronal RECEPTOR CELLS.
*live partly in the PNS and partly in the CNS

Front 26

Motor neurons

Back 26

end directly on muscles, glands, or other neurons in PNS ganglia.
*live partly in the PNS and partly in the CNS

Front 27

Interneurons

Back 27

2 types: Local and Projection
Local have all their processes confined to a single small area of the CNS

Front 28

Projection neurons

Back 28

Have long axons connection different areas
-ie: a neuron in the cerebral cortex whose axon reaches the spinal cord

Front 29

The human nervous system is comprised almost entirely of...

Back 29

interneurons and projection neurons (more than 99%)
*no more than 20 million sensory fibers
*no more than a few million motor neurons

Front 30

Lable A-D
Green arrows...
Blue arrows...

Back 30

A- multipolar Purkinje cell from teh cerebellar cortex
B- multipolar granule cell from the cerebellar cortex
C- multipolar projection neuron from the ingerior olivary nucleus
D- multipolar spinal cord motor neuron
Green arrows: dendrites
Blue arrows: axons

Front 31

Label F and G

Back 31

F- bipolar olfactory receptor neuron
G- unipolar Dorsal root ganglion cells

Front 32

Gray Matter

Back 32

areas where there is a preponderance of cell bodies and dendrites; neurons interconnecting (abundant blood supply)
-stains blue with copper sulfate

Front 33

Gray matter...

Back 33

Stained blue.
Note: cerebral cortex (outer bark of the cerebrum)
Note: deep nuclear structures (basal ganglia or basal nuclei)

Front 34

Gray Matter contains...

Back 34

Collections of nerve cell bodies (somas)
Interneurons
Projection Neurons
Motor Neurons
Endings of sensory fibers and fibers arriving from CNS

Front 35

Nuclei

Back 35

Concentrations of nerve cell bodies in CNS

Front 36

Ganglia

Back 36

Concentrations of nerve cell bodies in PNS

Front 37

White Matter

Back 37

areas where there is a preponderance of axons; many axons have a MYELIN sheath that is mostly lipids

Front 38

White Matter contains...

Back 38

Ascending and Descending pathways

Front 39

Dorsal/Ventral Horns
Dorsal/Ventral Roots
DRG
AG
Red arrow
Motor...
Sensory...

Back 39

Dorsal/Ventral Horns: H-shaped Gray matter
Dorsal/Ventral Roots: White matter
DRG: Dorsal Root Ganglion
AG: Autonomic ganglion
Red arrow: Projection neuron
MOTOR GOING OUT
SENSORY INFORMATION COMING INTO DORSAL HORN

Front 40

Afferent

Back 40

"Toward"
(a-attack)

Front 41

Efferent

Back 41

"Away"
(e-escape)

Front 42

Neuron Theory

Back 42

Ramon y Cajal on the basis of his histological research using Golgi staining
Neurons are discrete units and interconnected with each other for a communication network

Front 43

4 Brain Lobes:

Back 43

Frontal
Parietal
Occipital
Temporal

Front 44

Back 44

Front 45

Back 45

Front 46

Synapses

Back 46

Interconnect Neurons
Synapse or closely opposed neurons with a gap between them
Synapse is a term coined by Sir Charles Sherrington (British neurophysiologist).
Sherrington also won a Nobel prize a few years later.

Front 47

Types of Synapses
AD
AS
DD
AA1
AA2

Back 47

Named using pre/post-synaptic elements
AD- axodendridic, most synapses; axon terminal contacting a dendrite
AS- axosomatic
DD- dendrodendritic
AA1- axoaxonic synapses with the postsynaptic element being another axon terminal
AA2- postsynaptic element being the intial segment of an axon

Front 48

3-neuron circuit

Back 48

3-neuron circuit

Front 49

Types of Bipolar neurons

Back 49

In olfactory system
In inner ear (vestibular branch, cochlear branch)
In retina

Front 50

Spines

Back 50

The dendrites of many neurons are studded with small protuberances, which are the preferred sites for some kinds of synaptic contacts

Front 51

Types of Glial Cells (PNS)

Back 51

Schwann cells
S1 - forming myelin
S2 – engulfing unmyelined axons
*S3 - satellite cells (ganglionic gliocytes) (found in dorsal root ganglia & in autonomic ganglia

Front 52

Types of Glial Cells (CNS)

Back 52

Oligodendrocytes:
1. interfascicular (forming myelin)
2. satellite oligodendrocytes
Astrocytes:
1. protoplasmic
2. fibrous
3. radial glia
Ependyma
Microglia

Front 53

S1 wraps...

Back 53

a section of the myelinated axon
-node of Ranvier is at point "B" (end of axon)

Front 54

Oligodendroglia...

Back 54

wraps several different
neurons’ axons.

Front 55

Astrocyte

Back 55

end-feet on capillary surface promote
the formation of tight junctions between
endothelial cells (blood-brain barrier).

Front 56

Ependymal cells

Back 56

line the ventricles.
cover the surfaces of the choroid plexus which releases cerebrospinal fluid.

Front 57

Ventricles

Back 57

Spaces in the brain filled with CSF

Front 58

Back 58

Front 59

Gliosis

Back 59

When proliferating astrocytes in the region of a brain injury will form a pathophysiological locus or lesion causing focal epilepsy