Chapter 10 Muscular System

Question 1

Prime Mover (Agonist)

Answer 1

Muscle that contracts to provide most of a desired movement

Question 2

Synergists

Answer 2

Work with a prime mover to make its action more effective by adding a small amount of additional force

Question 3

Fixators

Answer 3

Help maintain upright posture

Question 4

Convergent muscles

Answer 4

Muscle fascicles extend over broad area, converging on a single attachment site. May pull on a tendon, aponeurosis. Ex: Pectoralis major (triangular/fan-shaped)

Question 5

Pennate Muscles

Answer 5

Fascicles create a common angle with tendon and muscle fibers pull at an angle. Do not move tendons as far as parallel muscles do but have more tension due to more muscle fibers/myofibrils. (Bipennate,multipennate)

Question 6

Circular muscles

Answer 6

Arranged around opening in a concentric pattern. Muscle contractions cause a decrease in the diameter of the opening. (Anus,mouth,eye)

Question 7

Fast fibers

Answer 7

Reach peak twitch in .01 seconds. Large in diameter. Large reserves of glycogen. Fatigue quickly.

Question 8

Slow fibers

Answer 8

1/2 diameter of fast fibers. Take 3x as long to reach peak tension. Can contract longer. Much higher o2 supply to support. (Red muscles)

Question 9

Axial Muscles

Answer 9

Affect head, spinal column, rib cage. Allow positioning of head/spinal column, move rib cage, and assist breathing process. DO NOT move body, support pelvic/pectoral girdle. Make up about 60% skeletal muscle.

Question 10

Appendicular Muscles

Answer 10

Stabilize and move appendicular skeleton and make up remaining 40% of skeletal muscle.

Question 11

Masseter Muscle

Answer 11

Strongest jaw muscle.

Question 12

Major muscle that moves the arm

Answer 12

Deltoid is the major abductor.

Question 13

Gluteus Maximus

Answer 13

Major extensor of the thigh

Question 14

Muscle reaches maximum size

Answer 14

At age 25