Skeletal Muscle

Question 1

What is the epimysium?

Answer 1

A layer of connective tissue that surrounds the whole muscle

Question 2

What is the perimysium?

Answer 2

A layer of connective tissue that surrounds each fascicle or bundle of muscle fibers.

Question 3

What is the endomysium?

Answer 3

Connective tissue that surrounds an individual muscle fiber.

Question 4

In muscle attachment, what is the origin?

Answer 4

The attachment site where the bone remains immobile.( There are some exceptions to this)

Question 5

What is the insertion?

Answer 5

The attachment site where the bone moves in response to muscle contraction

Question 6

What are hypaxial muscles?

Answer 6

Also called extrinsic muscles. The muscles of the back that are innervated by ventral rami.

Most superficial layers of the back just deep to skin.

Question 7

List the extrinsic back muscles

Answer 7

Latissimus dorsi
Rhomboid major and minor
Levator scapulae
Serratus posterior
Serratus inferior
Trapezius

Question 8

List the extrinsic back muscles.

Answer 8

Trapezius
Latissimus dorsi
Rhomboid major and minor
Levator scapulae
Serratus anterior
Serratus posterior Superior
Serratus posterior inferior

Question 9

What does a spinal nerve divide into?

Answer 9

The dorsal and ventral rami

Question 10

What combines to form a spinal nerve? What does each component carry

Answer 10

The dorsal root which receives sensory information and the ventral root which sends out motor impulses.

This is described in Bell Magendie’s law

Question 11

What is white matter made of?

Answer 11

Tracks, myelinated axons

Question 12

What is gray matter made of?

Answer 12

Cell bodies, form a butterfly shape in spinal column

Question 13

What is a dermatome?

Answer 13

A dermatome is a specific area of skin that is supplied by a single spinal nerve dorsal root. They are arranged in a segmental pattern.

Question 14

What is a muscle fiber

Answer 14

A muscle fiber is another name for a muscle cell, or myocyte.

Question 15

What is a muscle fascicle?

What does each fascicle have?

Answer 15

A collection of muscle fibers organized and bundled together. Each fascicle has its own nerve and blood supply

Question 16

What is the first branch off the arch of the aorta? And what do the components of its name mean?

Answer 16

The brachiocephalic trunk

Brachio means arm
Cephalic means head
And trunk implies that it will Branch

Question 17

What does the brachiocephalic trunk divide into? And where does each branch go?

Answer 17

The brachiocephalic trunk divides into:

Right Subclavian artery which goes to the shoulder and arm

Right common carotid artery which goes to the Head

Question 18

What is the second branch off the arch of the aorta?

Answer 18

The left common carotid artery

Question 19

What is the third branch off the Arch of the aorta?

Answer 19

The left subclavian artery

Question 20

What is an aponeurosis?

Answer 20

A flat sheet of tendon-like tissue that anchors muscle over a broad origin. Fibrous tough white and shiny.

Question 21

What is another name for the thoracolumbar fascia? Where is it located?

Answer 21

Also called the thoracolumbar aponeurosis. It is located in the lumbar and thorax regions.

Question 22

What are the layers of the thoracolumbar fascia?

Answer 22

Posterior layer: visible deep to skin, covers erector spinae muscles, attaches to spinous processes.

Middle Layer: attaches to transverse processes runs between erector spinae muscles and quadratus lumborum.

Anterior Layer: attaches to transverse processes runs deep to quadratus lumborum.

Question 23

What is the ligamentum nuchae? Where does it attach?

Answer 23

The ligamentum nuchae is a bilaminar ligament.

Attachment: to the EOP median nuchal line, and spinous processes of C1 through C7.

Question 24

What is the function of the ligamentum nuchae?

Answer 24

To provide attachment for trapezius rhomboids and intrinsic muscles.

Passively supports the head in extension.