Organization Of The Human Nervous System

Question 0

Peripheral Nervous System (PNS)

Answer 0

The part of the vertebrate nervous system that is located outside the skull and spine

Question 1

Central Nervous System (CNS)

Answer 1

The part of the vertebrae nervous system that is located within the skull and spine

Question 2

Cervical region

Answer 2

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

Question 3

Thoracic region

Answer 3

The section of the spine to which the ribs are attached; it lies between the cervical and the lumbar regions

Question 4

Lumbar region

Answer 4

The section of the spine that supports the small of the back; it lies between the thoracic region and the sacral region

Question 5

Sacral region

Answer 5

The section of the spine to which the bones of the pelvis are attached; it lies adjacent to the lumbar region

Question 6

Functions of the PNS

Answer 6

• conducts sensory signals to the CNS from sensory receptors in various parts of the body
• conducts motor signals away from the CNS to muscles, glands, and other effector organs in various parts of the body

Question 7

Brain

Answer 7

The part of the central nervous system that is located in the skull

Question 8

Spinal cord

Answer 8

The part of the central nervous system that is located in the spine

Question 9

Divisions of the Central Nervous System

Answer 9

The brain and the spinal cord

Question 10

Functions of the spinal cord

Answer 10

• receives signals from the sensory fibers of the PNS and conducts them to the brain for complex analysis
• receives signals from the brain and conducts them to the motor fibers of the PNS
• performs the simple rapid analyses that mediate many of our reflexive responses

Question 11

Somatic nervous system

Answer 11

The division of the 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 12

Autonomic nervous system

Answer 12

The 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 the receptors in internal organs, and motor signals from the CNS back to the same internal organs

Question 13

Spinal gray matter

Answer 13

The H-shaped area of gray nervous tissue in the core of the spinal cord

Question 14

Spinal white matter

Answer 14

The area of white nervous tissue in the spinal cord; it surrounds the spinal gray matter

Question 15

Dorsal roots

Answer 15

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

Question 16

Ventral roots

Answer 16

The 31 pairs of motor nerves that exit the spinal cord; they project from the spinal cord’s ventral surface

Question 17

Afferent nerves

Answer 17

Nerves that carry signals toward a structure (in regard to the structure)

Question 18

Efferent nerves

Answer 18

Nerves that carry signals away from a structure (in regard to the structure)

Question 19

Sympathetic nervous system

Answer 19

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

Question 20

Parasympathetic nervous system

Answer 20

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

Question 21

Pituitary gland

Answer 21

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

Question 22

Hypothalamus

Answer 22

The brain structure from which the pituitary is suspended; it secretes releasing hormones, which stimulate the release of tropic hormones from the pituitary

Question 23

Adrenal medulla

Answer 23

The core of the adrenal gland; it is activated by the sympathetic nervous system, and in turn it secretes hormones whose effects are similar to those of the sympathetic nervous system

Question 24

Adrenal cortex

Answer 24

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

Question 25

Gonads

Answer 25

The sex glands (i.e., ovaries in women and testes in men); they release hormones that influence both the development of female and male reproductive systems and the reproductive behavior of adults