Module 3 Overview

Question 1

Nervous system functions

Answer 1

• sensory input
• interpretive and integrative functions
• Motor output
• higher mental functioning and emotional responsiveness

Question 2

Nervous system is split into… (2)

Answer 2

Central nervous system and peripheral nervous system

Question 3

Central nervous system includes… (4)

Answer 3

• brain
• meninges
• cerebrospinal fluid (CFS)
• spinal cord

Question 4

2 divisions of Peripheral nervous system (PNS)

Answer 4

• somatic nervous system ( consciously controlled )
• autonomic nervous system

Question 5

2 divisions of autonomic nervous system

Answer 5

Parasympathetic (rest & digest)
Sympathetic (fight or flight)

Question 6

The peripheral nervous system has __ pairs of nerves: ___ cranial and ___ spinal

Answer 6

43 pairs, 12 cranial, 31 spinal

Question 7

Major regions of brain (4)

Answer 7

• cerebrum
• diencephalon
• cerebellum
• brain stem

Question 8

There are 2 types of cells in the nervous system: neurons and neuroglia (glial cells). What are key differences between them?

Answer 8

Neurons conduct nerve impulses. Neuroglia cannot.
Neuroglia never lose their ability to divide.

Neuroglia cells support, nourish, protect, insulate, and organize neurons.

Question 9

Neuroglia:

_________ produce myelin around axons in the CNS

_________ produce myelin around axons in the PNS

Answer 9

Oligodendrocytes (CNS)

Schwann Cells (PNS)

Question 10

3 parts of a neuron

Answer 10

Dendrites (transmit impulse —> toward —> cell body)
Cell body
Axon ( carry the nerve impulse AWAY from cell body)

Question 11

The gaps in the myelin sheath are called _______

Answer 11

Nodes of ranvier

Question 12

The functional unit of the nervous system is called…

Answer 12

Reflex arc

Question 13

A reflex arc consists of these 3 neurons

Answer 13

• afferent
• interneuron
• efferent

Question 14

What is an afferent nerve?

Answer 14

A sensory nerve that carries impulses/signals to brain or spinal cord and UP the spinal column

Question 15

What is an efferent neuron?

Answer 15

Carry message from brain to spinal cord to muscle or gland. Signals travel DOWN the spinal column

Question 16

What is the function of an interneuron?

Answer 16

Process information

Question 17

Connective tissue components of nerves:

1. _________ surrounds each nerve fibre (SMALLEST)
2. _________ surrounds groups of fibres (fascicles)
3. _________ surrounds groups of fascicles, forming a nerve

Answer 17

1. Endoneurium (Endo = inside, within)
2. Perineurium (Peri = around, near)
3. Epineurium (Epi = over, above)

Question 18

Define summation

Answer 18

The amount of stimuli needed to reach threshold stimulus

Question 19

Define threshold

Answer 19

The minimum level of intensity a stimulus must reach to generate a nerve impulse

Question 20

What is myelin?

Answer 20

A white layer of cells that surrounds axons to insulate and increase the speed of impulses

Question 21

Continuous conduction: nerve impulses travel along _______ axons and is ________ than saltatory conduction

Answer 21

Unmyelinated axons; slower

Question 22

Saltatory conduction: nerve impulses travel along ________ axons and is ______ than continuous conduction

Answer 22

Myelinated; faster

Question 23

The sodium potassium pump exchanges sodium and potassium at a ratio of ____

Answer 23

3:2

Question 24

Meninges are connective tissue covering the brain and spinal cord. Name the 6 layers and spaces from INNER to OUTER.

Answer 24

INNER (DEEPEST LAYER)

Pia Mater
Subarachnoid space
Arachnoid
Subdural space
Dura mater
Epidural space

OUTER (MOST SUPERFICIAL)