Organization of the Human Nervous System

Question 1

Central nervous system (CNS)

Answer 1

Part of the vertebrate nervous system that is located within the skull and spine.

Question 2

Peripheral nervous system (PNS)

Answer 2

Part of the vertebrate nervous system that is located outside the skull and spine.

Question 3

Cervical region (SIR-vi-cal)

Answer 3

Section of the spine that provides the flexible framework of the neck or cervix; it lies between the skull and the thoracic region.

Question 4

Thoracic region (thor-ASS-ic)

Answer 4

Section of the spine to which the ribs are attached; it lies between the cervical and the lambar regions.

Question 5

Lumbar region (LUM-bar)

Answer 5

Section of the spine that supports the small of the back; it lies between the thoracic region and the sacral region.

Question 6

Sacral region (SAK-ral)

Answer 6

Section of the spine to which the bones of the pelvis are attached; it lies adjacent to the lumbar region.

Question 7

Brain

Answer 7

Part of central nervous system that is located in the skull.

Question 8

Spinal cord

Answer 8

Part of central nervous system that is located in spine.

Question 9

Somatic nervous system (soe-MA-tic)

Answer 9

Division of peripheral nervous system that interacts with the external environment; it conducts sensory signals to the CNS from external receptors and receptors in joints and skeletal muscles, and it conducts motor signals from the CNS to skeletal muscles.

Question 10

Autonomic nervous system (aw-tuh-NOM-ik)

Answer 10

Division of the peripheral nervous system that participates in the regulation of the body’s internal environment; it conducts sensory signals to the CNS from receptors in internal organs, and motor signals from the CNS back to all the same internal organs.

Question 11

Spinal grey matter

Answer 11

H-shaped area of grey nervous tissue in the core of spinal cord.

Question 12

Spinal white matter

Answer 12

Area of white nervous tissue in the spinal cord; it surrounds the spinal grey matter.

Question 13

Dorsal roots

Answer 13

The 31 pairs of sensory nerves that enter the spinal cord; they enter the spinal cord’s dorsal (back) surface)

Question 14

Ventral roots

Answer 14

The 31 pairs of motor nerves that exit the spinal cord; they project from the spinal, cord’s ventral (front) surface.

Question 15

afferent

Answer 15

Carry signals toward a structure.
sensory nerve

Question 16

efferent

Answer 16

carry signals away from a structure.
motor nerve

Question 17

Sympathetic nervous system

Answer 17

One of the two motor divisions of the autonomic nervous system; it tends to mobilize energy resources during times of threat; sympathetic nerves project from the thoracic and lumbar regions of the spinal cord.

Question 18

Parasympathetic nervous system

Answer 18

One of the two motor divisions of the autonomic nervous system, it tends to conserve energy during pereiod s of quiescence; parasympathetic nerves project from the brain and from the sacral region of the spinal cord.

Question 19

Pituitary gland (pi-TUE-i-tair-ee)

Answer 19

Gland that hangs from the hypothalamus; because it releases tropic hormones, it is often referred to as the master gland.

Question 20

Hypothalamus (HIPE-oh-THAL-a-mus)

Answer 20

Brain structure from which the pituitary is suspended; it secretes releasing hormones. which stimulate the release of tropic hormones from the pituitary.

Question 21

Adrenal medulla

Answer 21

Core of the adrenal gland; it is activated by the sympathetic nervous system, and in turn it secretes hormones whose effects are similar (but last longer) than those if the sympathetic nervous system

Question 22

Adrenal cortex

Answer 22

Outer layer of the adrenal gland; it releases hormones that regulate energy metabolism, mineral balance, and reproductive behavior

Question 23

Gonads

Answer 23

Sex glands (ovaries or testes); they release hormones that influence both the development of female and male reproductive systems and the reproductive behavior of adults.