Chapter 12- Fundamentals of the Nervous System

Question 1

Functions of the Nervous System

Answer 1

Sensory Reception
Integration
Elicit Response

Question 2

Divisions of the Nervous System

Answer 2

Central (CNS)- Brain and Spinal Cord
Peripheral (PNS)- Everything else

Question 3

Divisions of the Peripheral Nervous System

Answer 3

Somatic- Body as a whole
Visceral- Internal organs
Sensory (Afferent)- Toward CNS
Motor (Efferent) Away from CNS

Question 4

Somatic Sensory Functions

Answer 4

Most sensory experiences
Touch, pain, pressure, vibration, temperature, proprioception
Hearing, equilibrium, vision

Question 5

Visceral Sensory Functions

Answer 5

State of internal environment
Stretch, pain, temperature, chemical changes, visceral irritation, nausea, hunger
Taste and smell

Question 6

Somatic Motor Function

Answer 6

Control of skeletal muscles

Question 7

Visceral Motor Functions

Answer 7

Control smooth and cardiac muscles
Control glands
Autonomic Nervous System

Question 8

Neurons

Answer 8

Basic communication cell
Dendrites- Receive information
Cell body (Soma)- Control center
Axon- Generate and conduct impulse

Question 9

Characteristics of Neurons

Answer 9

Conductive
Longevity- Live for a long time
Do not divide
High metabolism

Question 10

Structural Classifications of Neurons

Answer 10

Multipolar
Bipolar
Unipolar

Question 11

Multipolar Neurons

Answer 11

Many dendrites with one axon
Motor and interneurons

Question 12

Bipolar neurons

Answer 12

1 dendrite and 1 axon
Found only in special senses

Question 13

Unipolar (Pseudounipolar) neurons

Answer 13

One short, singular process
Cell body is on the side of the central process
Sensory Neurons

Question 14

Functional Classification of Neurons

Answer 14

Sensory (afferent)
Motor (efferent)
Interneurons (Association)

Question 15

Sensory Neurons

Answer 15

Transmit impulses toward the CNS
Mostly unipolar
Cell bodies found in the PNS in ganglia

Question 16

Motor Neurons

Answer 16

Transmit impulses away from the CNS; Junction with effector cells
Mostly multipolar
Cell bodies in the CNS in nuclei; Anterior gray matter

Question 17

Interneurons

Answer 17

Transmit impulses within the CNS
Mostly multipolar
Cell bodies in the CNS in nuclei; posterior gray matter

Question 18

Action potential

Answer 18

Electrical impulse that forms the basis of neuron communication
Depolarization of the cell

Question 19

Synapses

Answer 19

Junction between neurons
Types:
Axodendritic- Axon & Dendrite
Axosomatic- Axon & Cell body

Question 20

Synaptic potentials

Answer 20

Excitatory Synapses- Promotes depolarization and impulse generation
Inhibitory Synapses- Promotes hyperpolarization and restricts impulse generation

Question 21

Neuroglial cells

Answer 21

Support cells
Non-excitable, maintenance, and insulator cells
Outnumber neurons 10:1

Question 22

Neuroglia in the CNS

Answer 22

Astrocytes
Microglia
Ependymal cells- Line cavities and circulate cerebrospinal fluid
Oligodendrocytes- Insulatory cell that surrounds many axons

Question 23

Neuroglia in the PNS

Answer 23

Satellite cells- Surround neuron cell bodies in ganglia
Schwann Cells (neurolemmocytes)- Insulatory cells

Question 24

Myelin Sheaths

Answer 24

Surround axon to insulate and prevent current leakage
Increases impulse velocity

Question 25

Multiple Sclerosis

Answer 25

Autoimmune disease that targets oligodendrocytes and myelin in the CNS

Question 26

Nerves

Answer 26

Cordlike organ in the PNS made of many axons wrapped in connective tissue containing blood supply

Question 27

Tracts

Answer 27

Nerve equivalents in the CNS Many axons travelling in a similar direction

Question 28

Reflex Arcs

Answer 28

Allow for rapid automatic responses Components: Receptor, sensory neuron, (interneuron), motor neuron, effector Monosynaptic- No interneuron Polysynaptic- With interneuron

Question 29

Neuronal Circuits

Answer 29

Diverging- One neuron impacts many (Ex- Fight or flight) Converging- Many neurons act on one (most neurons) Reverberating- Self-stimulating feedback loop (ex- breathing)

Question 30

Gray matter

Answer 30

No myelination; Location of cell bodies Spinal gray matter- Internal Brain gray matter- External

Question 31

White matter

Answer 31

Myelinated axons Spinal white matter- External Brain white matter- Internal

Question 32

Neuron regeneration

Answer 32

Only possible in the PNS if the cell body remains intact Steps: 1) Macrophages invade and destroy axon distal to injury 2) Axon filaments grow into tube formed by Schwann cells 3) Axon regenerates and myelin sheath surrounds axon