Chapter 3 part 1

Question 1

Central Nervous System (CNS)

Answer 1

The portion of the nervous system within the skull and spine. Composed of two divisions: the brain and the spinal cord.

Question 2

Peripheral Nervous System (PNS)

Answer 2

The portion of the nervous system outside the skull and spine. Comprised of two divisions: the somatic nervous system and the autonomic nervous system.

Question 3

Somatic Nervous System (SNS)

Answer 3

The part of the peripheral nervous system that interacts with the external environment. It is comprised of afferent nerves that carry sensory signals from the skin, skeletal muscles, joints, eyes, ears, and so on to the central nervous system and efferent nerves that carry motor signals from the central nervous system to the skeletal muscles.

Question 4

Autonomic Nervous System (ANS)

Answer 4

The part of the peripheral nervous system that regulates the body’s internal environment. It is composed of afferent nerves that carry sensory signals from internal organs to the CNS and efferent nerves that carry motor signals from the CNS to internal organs.

Question 5

Sympathetic Nerves

Answer 5

Autonomic motor nerves that project from the CNS in the lumbar (small of the back) and thoracic (chest area) regions of the spinal cord.

Sympathetic nerves stimulate, organize, and mobilize energy resources in threatening situations.

Sympathetic changes are indicative of psychological arousal.

Question 6

Parasympathetic Nerves

Answer 6

Those autonomic motor nerves that project from the brain and sacral (lower back) region of the spinal cord.

Parasympathetic nerves act to conserve energy.

Parasympathetic changes are indicative of psychological relaxation.

Question 7

Cranial Nerves

Answer 7

The 12 pairs of nerves extending from the brain (e.g., the optic nerves, the olfactory nerves, and the vagus nerves).

Question 8

Cranial Nerves 1 - 5

Answer 8

I: olfactory 
II: optic 
III: oculomotor
IV: trochlear
V: abducens

Question 9

Meninges

Answer 9

The three protective membranes that cover the brain and spinal cord (singular meninx).

Question 10

Dura Mater (tough mother)

Answer 10

The tough outer meninx.

Question 11

The autonomic nervous system has two kinds of efferent nerves:

Answer 11

Sympathetic nerves and parasympathetic nerves.

Question 12

Blood-brain barrier

Answer 12

A mechanism that impedes the passage of many toxic substances from the blood into the brain.