Parts of the Nervous System (Ch. 18)

Question 1

Bipolar Neurons

Answer 1

Conduct information along sensory pathways.
- eyes
- inner ear
- olfactory

Question 2

Multipolar Neurons

Answer 2

Conduct impulses along motor pathways.

Question 3

Unipolar Neurons

Question 4

Ependymal Cells

Answer 4

• Line the fluid-filled spaces of the brain and
  spinal cord.
• Responsible for producing CSF.

Question 5

Oligodendrocytes

Answer 5

Form insulating myelin sheath around CNS nerve fibers.

Question 6

Schwann Cells

Answer 6

Form insulating myelin sheath around PNS nerve fibers.

Question 7

Central Nervous System

Answer 7

Brain and spinal cord
- Integrates incoming information

Question 8

Somatic Nervous System

Answer 8

Subdivision of the PNs that controls voluntary activities, such as the activation of skeletal muscles.

Question 9

Peripheral Nervous System

Answer 9

Cranial and spinal nerves

Question 10

Autonomic Nervous System

Answer 10

Subdivision of the PNS that regulates the activity of cardiac muscle, smooth muscle, and glands.

Question 11

Neuroglia

Answer 11

Supporting cells found in the CNS.

Question 12

Primary characteristics of neurons

Answer 12

• Excitablility
• Conductivity

Question 13

Macrophages

Answer 13

Engulf invading microorganisms and dead neural tissue.

Question 14

Neurotransmitters

Answer 14

Chemicals released by neurons that stimulate other neurons or muscles.

Question 15

Tract

Answer 15

A bundle of axons in the CNS.

Question 16

Motor neurons (efferent)

Answer 16

Transmit impulses for the CNS to the muscles and glands.

Question 17

Sensory neurons (afferent)

Answer 17

Transmit impulses from the sensory receptors to the spinal cord.

Question 18

Interneurons

Answer 18

• Only in the CNS

Question 19

Sympathetic Nervous System

Answer 19

• Subdivision of the ANS
• “Fight or flight” responses

Question 20

Parasympathetic Nervous System

Answer 20

• Subdivision of the ANS
• Coordinates body’s normal resting activities

Question 21

Enteric Nervous System

Answer 21

• Subdivision of the ANS
• Provides feedback to and from the GI tract

Question 22

Astrocytes

Answer 22

Star-shaped, largest and most numerous type of glia.
- Only in the CNS
- Transfer nutrients to the neuron
- Help restore normal ion gradients
during intense neuron activity.
- (recycle neurotransmitters)
- Create the blood-brain barrier
*tight gap junctions

Question 23

Microglia

Answer 23

Small cells of the CNS.
- Usually stationary
- Constantly scavenging the CNS for
damaged neurons, plaques, and
infectious agents.
- Carry out phagocytosis in inflamed
or degenerating brain tissue.
- May play a role in “pruning” during
development to increase efficiency
of neural circuits.

Question 24

Reflex

Answer 24

Fast, involuntary, unplanned sequence of actions that occurs in response to a particular stimulus.

Question 25

Reflex arc

Answer 25

The pathway followed by nerve impulses that produces a reflex.

Question 26

5 components of a reflex arc

Answer 26

1) Sensory receptor (stimulus)
2) Sensory (affferent) neuron
3) Interneuron (integrating center)
4) Motor (efferent) neuron
5) Effector (response)