Quiz 9: Sidman (Ch 49)

Question 1

The gray matter of the spinal cord is continuous with the gray matter of the medulla. In each picture on the right, the arrow points to the _____ _____, and the large area within the heavy outline is composed mainly of _____ matter.

Answer 1

central canal; gray

Question 2

The spinal nucleus of V, located in the medulla and upper part of the _____ region of the spinal cord, is continuous with components of the _____ horns at lower levels of the spinal cord. In the same way, some of the motor components of the brainstem are continuous with components of the _____ horns of the cord.

Answer 2

cervical; posterior; anterior

Question 3

Note the position of the central canal relative to the encircled nucleus on the right hand picture. The cells in this nucleus are similar in position and function to cells of the _____ horn of the spinal cord. The cell bodies in the encircled area are _____ in function.

Answer 3

anterior; motor

Question 4

In the spinal cord, motor neurons are anterior to the central canal, and sensory neurons are posterior. In the upper medulla, the _____ ventricle becomes wide. The motor nuclei remain in the same relative position, near the midline and _____ior to the ventricle. The sensory nuclei are displaced by the expanding ventricle to a more anterior and _____ position.

Answer 4

4th; anterior; lateral

Question 5

There are three groups of motor nuclei in the brainstem: somatic, branchial, and visceral. They innervate two types of muscle; somatic motor nuclei and branchial motor nuclei both innervate skeletal muscle, whereas visceral motor nuclei innervate smooth muscle of viscera, vessels, and glands. _____ and _____ motor nuclei innervate _____ muscle.

Answer 5

Somatic; branchial; skeletal

Question 6

The two groups of brainstem motor nuclei that innervate skeletal muscles are distinguished on the basis of the embryonic origin of the muscles they innervate; one group innervates muscle derived from somites, whereas the other group innervates muscle derived from branchial (pharyngeal) arches. Which group of brainstem motor nuclei innervates skeletal muscle derived from embryonic somites? _____ Skeletal muscles originating in branchial/pharyngeal arches of the embryo are innervated by the _____ group of motor nuclei.

Answer 6

Somatic; branchial

Question 7

Smooth muscle, much of it found in the walls of blood vessels and in the viscera of the thorax and abdomen, is supplied by the _____ motor nuclei of the brainstem.

Answer 7

visceral

Question 8

In contrast to skeletal muscles, smooth muscles and glands are innervated by the _____ motor nuclei. Skeletal muscles located in the head and neck are innervated by _____ and _____ nuclei of the brainstem.

Answer 8

visceral; somatic; branchial

Question 9

Embryonic somites give rise to the extraocular muscles and the intrinsic muscles of the tongue. Somatic motor nuclei innervate muscles involved in movements of the _____ and _____.

Answer 9

eye; tongue

Question 10

The extraocular muscles are attached to the _____side of the eye; their function is to _____ the eyeball. The intrinsic muscles of the tongue are located _____side the tongue; their function is to _____ the tongue.

Answer 10

outside; move; inside; move

Question 11

Somites give rise to the intrinsic muscles of the _____ and to the _____ muscles.

Answer 11

tongue; extraocular

Question 12

The sternocleidomastoid and trapezius muscles arise from branchial/pharyngeal arches. The _____mastoid and _____ muscles are supplied by _____ motor nuclei.

Answer 12

sternocleidomastoid; trapezius; branchial

Question 13

Most skeletal muscles of the face and neck originate in pharyngeal arches. The most inferior of these are the sternocleido_____ and trapezius muscles.

Answer 13

sternocleidomastoid

Question 14

The muscles of the throat also originate from pharyngeal arches; muscles of the larynx and _____rynx are innervated by _____ motor nuclei.

Answer 14

pharynx; branchial

Question 15

Branchial and somatic motor nuclei supply muscles used in vocalization. A branchial nucleus innervates the _____; a somatic nucleus innervates the _____.

Answer 15

larynx; tongue

Question 16

Branchial motor nuclei innervate two neck muscles, the _____ and _____, and also innervate skeletal muscles of the _____ and _____. Other pharyngeal arches give rise to the upper and lower jaws and related soft tissues of the face; branchial motor nuclei supply the muscles of mastication and the muscles of _____ expression.

Answer 16

sternocleidomastoid; trapezius; larynx; pharynx; facial

Question 17

Although the muscles supplied by the branchial motor nuclei are striated (skeletal), some of them are functionally associated with the alimentary system. These are the muscles of _____tication and the muscles of the _____.

Answer 17

mastication; pharynx

Question 18

Viscera, vessels, and glands of the head and the two major body cavities, the _____ax and _____men, are innervated by the _____ motor nuclei of the brainstem.

Answer 18

thorax; abdomen; visceral

Question 19

The pupillo-constrictor muscle of the iris is smooth muscle and is innervated by a _____ motor nucleus of the brainstem. The pupillo-constrictor muscle acts to make the pupil of the eye _____er in size.

Answer 19

visceral; smaller

Question 20

A visceral motor nucleus innervates the pupillo-constrictor muscle of the iris _____side the eye; somatic motor nuclei innervate the _____ muscles of the eye.

Answer 20

inside; extraocular

Question 21

Visceral motor nuclei innervate the salivary _____. The heart and involuntary (smooth) musculature of the respiratory passages, esophagus, stomach, and small intestines are all innervated by a single _____ motor nucleus of the brainstem.

Answer 21

glands; visceral

Question 22

Use the letters “S,” “B,” and “V” to indicate which of the three groups of brainstem motor nuclei innervates each of the following:

Sternocleidomastoid and trapezius muscles:
Tongue muscles:
Smooth muscles of the thorax and abdomen:
Extraocular muscles:
Muscles of facial expression:
Salivary glands:
Muscles of mastication:
Striated muscles of the pharynx and larynx:
Pupillo-constrictor muscle:

Answer 22

B; S; V; S; B; V; B; B; V