Exam 2: Nervous System I Flashcards Preview

Anatomy A-215 > Exam 2: Nervous System I > Flashcards

Flashcards in Exam 2: Nervous System I Deck (35):
1

Central Nervous System

-brain and spinal cord
-control center
-president

2

Peripheral Nervous System (PNS)

-cranial nerves, spinal nerves and ganglia
-ganglion=group of neuron cell bodies located outside CNS
-workers

3

Sensory (afferent) Division

receives information FROM body and transmits it TO CNS for processing
-has both CNS and PNS parts

4

Somatic Sensory

-part of sensory division
-receives sensory information from skin, joints, muscle, special senses (vision, hearing, balance, smell, taste)

5

Visceral Sensory

-part of sensory division
-receives sensory info from blood vessels and viscera

6

Motor Division

transmits info FROM the CNS To muscles and glands
-has both CNS and PNS parts

7

Somatic Motor

-part of motor division
-innervate skeletal muscle
-voluntary

8

Autonomic Motor

-part of motor division
-innervates smooth muscle, cardiac muscle, and glands of viscera (organs)
-involuntary

9

Neurons

-respond to stimuli and conduct nerve impulses
-primarily amitotic

10

Glial Cells

-support and protect neurons
-many more glial cells than neurons
-divide by mitosis

11

Cell Body of Neuron

-function: neuron's control center or head

12

Nucleus

--houses DNA
-contains nucleolus for protein synthesis

13

Chromatophilic substances (Nissl bodies)

-rough ER inside cell body
-function: protein synthesis
-look like darkened clumps within cytoplasm
-no chromatophilic substance in axon hillock

14

Dendrites

-short nerve cell process
-function: receive input (incoming nerve impulses)
-send nerve cells to cell body
-neuron can have 1 or many dendrites

15

Axon

-long nerve cell process
-function: send output (outgoing nerve impulses
-one axon per neuron

16

Axon Hillock

-portion of the cell body from where the axon originates
-no chromatophilic substance here

17

Multipolar Neuron

-one axon and many dendrites
-most common
-ex: motor neurons, interneurons

18

Bipolar Neuron

-two processes: one axon and one dendrite
-limited in location (rare)
-ex: retina of eye, olfactory neurons in nose

19

Unipolar (Pseudounipolar) Neuron

-Single process comes off of the cell body and divides into two branches
-common
-most (not all) sensory neurons

20

Sensory (afferent) Neuron

-brings information TO CNS
-either unipolar or bipolar neurons

21

Motor (efferent) Neuron

-takes information FROM CNS to other parts of the body
-all are multipolar

22

Interneuron

-help coordinate and integrate info between sensory and motor neurons
-located solely in CNS
-"translator/mediator"
-multipolar in form

23

Neuron Classification

-by structure or by function

24

Satellite Cells

-In PNS
-surround neuron cell bodies in spinal ganglia
-protect the cell bodies
-regulate nutrient exchange and waste removal

25

Neurolemmocytes (Schwann Cells)

-myelinate axons in PNS
-myelin is a protective covering around axon that insulates axon and helps produce faster nerve impulses
-can also help regenerate damaged PNS axons

26

Astrocytes

-in CNS
-regulate transfer of materials from blood to the brain, help workings of BBB
-helps make blood vessels less leaky

27

Blood Brain Barrier

-keeps harmful substances away from brain
-selectively permeable
-bust some needed substances can't pass this barrier either like chemotherapy drugs

28

Astrocytes and the BBB (Parkinsons)

-caused by a decrease of a dopamine
-dopamine can't pass the BBB but a related drug, L-dopa, can.
-Cocaine and methamphetamine pass through and damage BBB

29

Oligodendrocytes

-myelinates multipe axons in CNS
-to CNS as neurolemmocytes are to PNS

30

Microglia

-phagocytize damaged neurons in CNS
-replicate when there is CNS damage and need to clean up an area

31

Ependymal Cells

-line central canal and ventricles of CNS
-help circulate CSF
-central canal and ventricles are spaces within the spinal cord and brain respectively

32

Myelination

-process of wrapping an axon with myelin
-myelin insulates axon, produces a faster nerve impulse
-dendrites are not myelinated

33

Myelination Procedure in PNS

-Neurolemmocyte wraps around a 1 mm portion of an axon successively
-Cytoplasm and nucleus of neurolemmocyte gets "squeezed" to the outside
-inner successive layers of cell membrane make up the myelin sheath of neurolemocyte

34

Neurofibril Nodes (Nodes of Ranvier)

-separate neurolemmocytes
-axon unmyelinated here
-nerve impulse is generated at these nodes

35

Myelination in CNS

-one oligodendroyte myelinates 1 mm portions of many axons
-similar to PNS but oligodendrocytes myelinate CNS axons