Muscular System Review Packet Name______

Anatomy & Physiology Period #______

1. On the diagrams below, draw a line to and label the muscles using the word bank below. You only need to label the muscle on either the posterior or anterior diagram. You can use the letter at the end of the line that you draw.

a. orbicularis oris b. pectoralis major c. external oblique

d. sternocleidomastoid e. biceps brachii f. deltoid

g. rectus femoris h. sartorius i. gracilis

j. adductor muscle k. temporalis l. orbicularis oculi

m. masseter n. tibialis anterior o. rectus abdominus

p. trapezius q. gluteus maximus r. gastrocnemius

s. latissimus dorsi t. deltoid u. biceps femoris

v. triceps brachii w. buccinator x. occipitalis

2. Number the following muscle structures in order from largest to smallest:

______myofibril ______myofilament ______sarcomere ______fascicle

______muscle ______muscle fiber

3. Label the diagram below with the following: myofibril, fascicle, epimysium, endomysium, perimysium, fiber, tendon

5. What is the difference between actin and myosin?

6. What produces striations in muscle fibers?

7. Draw and label a sarcomere below. Include the following labels:

I band A band H zone myosin

actin sarcomere Z line

8. What is the name of the site on a muscle fiber where a motor neuron connects?

9. Name the neurotransmitter that stimulates muscle contraction:

10. Physiologically, what causes a muscle contraction to stop?

11. What is the role of calcium in muscle contraction?

12. Explain the sliding filament theory.

13. What causes muscle fatigue?

Use the key below to match the description with the type of muscle for #15-24. Some numbers might have more than one letter. For these, write BOTH letters on the blank.

a. skeletal muscle b. smooth muscle c. cardiac muscle

15. ______striated

16. ______involuntary

17. ______muscle of the heart

18. ______found in antagonistic pairs

19. ______non-striated

20. ______fibers are short, branched, and interconnected

21. ______intercalated discs allow for “all-or-none” contractions

22. ______facilitate locomotion

23. ______joined to bones by tendons

24. ______lines the viscera of the body

25. Why is it that smooth muscle appears smooth even though it contains both actin and myosin?

26. What is the difference between origin and insertion?

27. What happens with the origin and insertion (in terms of movement) during a muscle contraction?

28. Why do muscles always work in antagonistic pairs?

Use the term bank below to answer the following. Some muscles may be used more than once or not all.

a. orbicularis oris b. pectoralis major c. external oblique

d. sternocleidomastoid e. biceps brachii f. deltoid

g. rectus femoris h. sartorius i. gracilis

j. adductor muscle k. temporalis l. orbicularis oculi

m. masseter n. tibialis anterior o. rectus abdominus

p. trapezius q. gluteus maximus r. gastrocnemius

s. latissimus dorsi t. deltoid u. biceps femoris

v. triceps brachii x. buccinator y. occipitalis

29. ______circular muscle that blinks and closes the eye

30. ______abducts, flexes, and extends the humerus

31. ______posterior arm, opposite biceps brachii

32. ______flexes neck and rotates head

33. ______most prominent muscle of the back

34. ______circular muscle around the lips

35. ______sides of face in front of ear

36. ______fan-shaped muscle of the chest

37. ______flexes forearm at elbow and rotates hand laterally

38. ______allows one to be able to “shrug” shoulders

39. ______the “six-pack”

40. ______runs diagonally from the hip to the medial surface of the tibia