Nervous Tissue

Question 1

Neurology

Answer 1

The study of the nervous system.

Question 2

Sensory Function

Answer 2

Detects external/internal stimuli.

Carries info to CNS

Question 3

Integration function

Answer 3

Analyzes sensory info and makes decisions on how to respond.
Connects sensory neurons to motor neurons (CNS).

Question 4

Motor function

Answer 4

Carries info from CNS to muscle contraction or gland secretion.

Question 5

Neurons

Answer 5

Nerve cell

Produce nerve impulse (action potential).

Question 6

Dendrite

Answer 6

Branches they receive info & carry nerve impulse to cell body.

Question 7

Cell body

Answer 7

Main part of neuron, contains nucleus & organelles.

Question 8

Axon

Answer 8

Usually single branch of neuron

Carries nerve impulse to next neuron, muscle, or gland.

Question 9

Axon terminal

Answer 9

Contains neurotransmitters which cross synapse & send impulse to next neuron, muscle, or gland.

Question 10

Myelin sheath

Answer 10

Covers axon
Composed of lipid & protein
Produced by Schwann cells (PNS) & oligodendrocytes (CNS)
Insulates axon &a increases speed of nerve impulse.

Question 11

Nodes of Ranvier

Answer 11

Gaps between the myelin sheaths

Nerve impulse jumps from one node to the next.

Question 12

Neuroglia (glia cells)

Answer 12

Make up about 1/2 of nervous system.

Function: support, nourish, & protect nerve cell.

Question 13

Types of neuroglia in CNS

Answer 13

1. Astrocytes
2. Oligodendrocytes
3. Microglia
4. Ependymal cells

Question 14

Types of neuroglia in PNS

Answer 14

1. Schwann cells

2. Satellite cells

Question 15

Astrocytes (CNS)

Answer 15

Support, maintain chemical balance around neuron, make “blood barrier,” & may be involved in learning and memory.

Question 16

Oligodendrocytes (CNS)

Answer 16

Form myelin sheaths

Question 17

Ependymal cells (CNS)

Answer 17

Produce, monitor, & aid in the circulation of cerebrospinal fluid.
Form blood-cerebrospinal fluid barrier

Question 18

Microglia (CNS)

Answer 18

Phagocytize bacteria, dead cells, & damaged nerve cells.
“Clean up crew”

Question 19

Schwann cells (PNS)

Answer 19

Form myelin sheaths for

Question 20

Satellite cells (PNS)

Answer 20

Support neurons, regulate exchanges of material between neuron cell bodies & interstitial fluid

Question 21

Unmyelinated axon

Answer 21

Continuous conduction
Impulse involves change occurring in axon membrane.

Grey matter

Question 22

Myelinated axon

Answer 22

Saltatory conduction
Impulse only changes membrane at nodes (faster).

White matter

Question 23

Multiple Sclerosis (MS)

Answer 23

Autoimmune disease that progressively destroys myelin sheaths.
Alternates between relapses & remissions.
Affects women more often than men.

Question 24

Nerve

Answer 24

Bundle of axons, dendrites, or both in PNS.

Most found in CNS

Question 25

Ganglion

Answer 25

Collection of cell bodies outside the CNS

Question 26

Tract

Answer 26

Bundle of axons in CNS Ascending - go up the spinal cord (sensory) Descending - go down the spinal cord (motor)

Question 27

Nucleus

Answer 27

Collection of cell bodies inside CNS

Question 28

Central Nervous System (CNS) composed of...

Answer 28

Brain & spinal cord

Question 29

CNS Function

Answer 29

Analyzes sensory info Generates thoughts & emotions Stores memories Controls muscles & glands

Question 30

Peripheral Nervous System (PNS) is composed of...

Answer 30

Nerves extending from brain & spinal cord (spinal nerves, cranial nerves, spinal plexus), ganglia, & sensory receptors

Question 31

PNS Function

Answer 31

Sensory - collects impulses & carries them to CNS | Motor - carries response away from CNA to organs, muscles, or glands

Question 32

Somatic nervous system (PNS)

Answer 32

Sensory neurons in skin, limbs, & sense organs (involuntary) Motor neurons to skeletal muscles (voluntary)

Question 33

Autonomic nervous system or ANS (PNS)

Answer 33

Involuntary Includes sensory & motor neurons (cardiac &a smooth muscles) & glands. ``` Sympathetic division (fight or flight) Parasympathetic division (rest & digest) ```

Question 34

Enteric nervous system (PNS)

Answer 34

Involuntary Controls GI tract Functions somewhat independently. Communicates with the CNS through sympathetic & parasympathetic neurons.