Chapter 11

Question 1

Define the skeletal muscle Origins.

Answer 1

“stationary” location

Question 2

Define the skeletal muscle insertions.

Answer 2

location on structure (on bone) brought closer to origin during contractions

Question 3

Define the skeletal muscle belly.

Answer 3

the fleshy portion between tendons

Question 4

What are the possible actions a muscle can play when it works with others?

Answer 4

• Prime mover/agonist
• Antagonist opposes/reverses
  Synergist = helps the prime mover by :
  - preventing unwanted movements
  - being a fixator which helps stabilize “fix” a joint bone
• Fixator (muscle that holds origin bone firmly in place)

Question 5

List the actions for Elbow Flexion.

Answer 5

Prime mover - brachialis
Synergist - biceps brachii
Antagonist - triceps brachii
Fixator - Rhomboids (muscle that holds scapular firmly in place)

Question 6

List the ways bones, muscles, and joints can work as levers.

Answer 6

• Lever (rigid bar moves) > bone
• Fulcrum (fixed point) > Joint
• Resistance (the load) > the part being moved
• Effort (force against the load) > Force of contraction

Question 7

What are the 3 classes levers can be classified ?

Answer 7

1st class (eFr)
2nd class (fRe)
3rd class (fEr)

Question 8

Fassicles - bundles of _________ that can be in different patterns.

Answer 8

MYOFIBERS

Question 9

What are the different fascicle arrangements ?

Answer 9

• Parallel (straplike/fusiform)
• Convergent, Triangular (fan shaped)(origin)
• Circular (rings)
• Pennate (feather shaped) (insertion into tendon)
• Unipennate (one side)
• Bipennate (two sides)
• Multipennate (all sides)

Question 10

List one example of each fascicle arrangement.

Answer 10

Parallel straplike- sternocleidomastoid
Parallel fusiform - biceps brachii
Convergent - pectorals major
Circular - orbicularis oris
Unipennate - flexor polilicus longus
Bipennate - rectus femoris
Multipennate - deltoid