Nervous System

Question 1

Central Nervous System

Answer 1

Consists of brain and spinal cord. Develop from neural tube in embryo

Question 2

Peripheral Nervous System

Answer 2

Composed of all nervous structures outside the CNS that conned the CNS to the body. Develop from neural crest cells and as outgrowths of CNS

Question 3

Gray matter

Answer 3

Containing cell bodies, consists of an outer portion of brain

Question 4

White matter

Answer 4

Made of axons forming tracts and pathways, inner portion of brain

Question 5

Ventricles

Answer 5

Spaces filled with cerebrospinal fluid

Question 6

Meninges

Answer 6

3 connective tissue coverings that surround, protect, and suspend the brain and spinal cord with the cranial cavity and vertebral canal respectively

Question 7

Dura mater

Answer 7

Thickest and most external of the meninges coverings

Question 8

Arachnoid mater

Answer 8

Against the internal surface of the dura matter

Question 9

Pia mater

Answer 9

Adherent to the brain and spinal cord

Question 10

Somatic part of CNS

Answer 10

Innervates structures derived from somites in embryo, mainly involved with receiving and responding to information from the external environment

Question 11

Visceral part of CNS

Answer 11

Innervates organ systems in the body and other visceral elements such as smooth muscle and gland in peripheral regions of body. Mainly concerned with detecting and responding to information from the internal environment

Question 12

Motor neurons develop from

Answer 12

cells within the spinal cord

Question 13

Sensory neurons develop from

Answer 13

neural crest cells

Question 14

Proprioception

Answer 14

Sense of determining the position and movement of the musculoskeletal system detected by special receptors in muscles and tendons

Question 15

Somatic sensory neurons

Answer 15

Carry information (temperature, pain, touch, and proprioception) from the periphery into the CNS. Called somatic sensory afferents or general somatic afferents

Question 16

Somatic motor fibers

Answer 16

Carry information away from the CNS to skeletal muscles. Called Somatic motor efferents or general somatic efferents

Question 17

Dermatome

Answer 17

Area of skin supplied by a single spinal cord level or on one side by a single spinal nerve

Question 18

Muscle moving shoulder joint are innervated mainly by spinal nerves from spinal cord levels

Answer 18

C5 and C6

Question 19

Muscles moving elbow are innervated mainly by spinal nerves from spinal cord levels

Answer 19

C6 and C7

Question 20

Muscles in the hand are innervated mainly by spinal nerves from spinal cord levels

Answer 20

C8 and T1

Question 21

Myotome

Answer 21

Region of skeletal muscle innervated by a single nerve or spinal cord level. Most individual muscles of body are innervated by more than one spinal cord level, so the evaluation of myotomes is usually accomplished by testing movements of joints or muscle groups

Question 22

Autonomic division of PNS consists of

Answer 22

sympathetic and parasympathetic parts

Question 23

Visceral sensory neurons arise from

Answer 23

neural crest cells, send processes medially into the adjacent neural tube and laterally into regions associated with the developing body (general visceral afferent fibers)

Question 24

Visceral motor neurons arise from

Answer 24

cells in lateral regions of the neural tube, send processes out of the anterior aspect of the tube (general visceral efferent fibers)

Question 25

Preganglionic motor neurons and fibers

Answer 25

Visceral motor neurons located in spinal cord and their axons

Question 26

Postganglionic motor neurons and fibers

Answer 26

Visceral motor neurons located outside the CNS and their axons

Question 27

Ganglion

Answer 27

Cell bodies of visceral motor neurons outside the CNS often associate with each other in a discrete mass

Question 28

Nerves in cranial region that visceral components exit

Answer 28

CN III, VII, IX, and X (4 of 12 cranial nerves) (parasympathetic)

Question 29

Nerves in spinal cord that visceral components exit

Answer 29

Spinal cord levels T1 through L2 (sympathetic) and S2 to S4 (parasympathetic)

Question 30

Sympathetic system

Answer 30

innervates structures in peripheral regions of the body and viscera

Question 31

Parasympathetic system

Answer 31

More restricted to innervation of the viscera only

Question 32

White ramus communicans

Answer 32

Carries pregagnlionic sympathetic fibers and appears white because the fibers it contains are myelinated. Connects anterior rami of T1 to L2 to sympathetic trunk

Question 33

Gray ramus communicans

Answer 33

Connects sympathetic trunk or a ganglion to the anterior rams and contains the postganglionic sympathetic fibers. Appears gray because nonmyelinated. Positioned medial to the white rams communicants. Associated with all spinal nerves

Question 34

Preganglionic sympathetic fibers that enter a paravertebral ganglion or the sympathetic trunk through a white rams communicants may take the following four pathways to target tissues:

Answer 34

1. Preipheral sympathetic innervation at the level of origin of the preganglionic fiber.
2. Peripheral sympathetic innervation above or below the level of origin of the preganglionic fiber. (may/may not have visceral motor input directly from spinal cord i.e. other than T1-L2)
3. Sympathetic innervation of thoracic and cervical viscera (mainly from spinal cord levels T1-T5 innervate cranial, cervical, and thoracic viscera.) Synapse with post ganglionic motor neurons in ganglia and then leave medially.
4. Sympathetic innervation of the abdomen and pelvic regions and the adrenals (without synapsing in sympathetic trunk to form splanchnic nerves derived from spinal cord levels T5 to L2, generally connect with sympathetic ganglia around roots of major arteries that branch from the abdominal aorta. Some pass through system to adrenal gland where synapse directly with cells of adrenal medulla)

Question 35

Paravertebral sympathetic trunk

Answer 35

Extends entire length of vertebral column, made of ascending and descending fibers together with all the ganglia

Question 36

Superior cervical ganglion

Answer 36

Highest ganglion in the neck, all sympathetics passing into the head have preganglionic fibers that emerge from spinal cord level T1 and ascend in the sympathetic trunks to the highest ganglion in the neck