The Muscular System

1. The Muscular System

2. Five Golden Rules of Skeletal Muscle Activity Table 6.2

3. Muscles and Body Movements • Movement is attained due to a muscle moving an attached bone • Muscles are attached to at least two points • Origin • Attachment to a moveable bone • Insertion • Attachment to an immovable bone

4. Muscles and Body Movements Figure 6.12

5. Collins I3 lines • What do you think the following terms mean in terms of body movement? • Flexion • Extension • Rotation • Can you demonstrate what each would look like by moving your body?

6. Agenda3/26/12---Day 1 • Discuss body movements • Notes • Facial muscles

7. Types of Ordinary Body Movements • Flexion • Decreases the angle of the joint • Brings two bones closer together • Typical of hinge joints like knee and elbow • Extension • Opposite of flexion • Increases angle between two bones

8. Types of Ordinary Body Movements Figure 6.13a

9. Types of Ordinary Body Movements Figure 6.13b

10. Types of Ordinary Body Movements

11. Types of Ordinary Body Movements • Rotation • Movement of a bone around its longitudinal axis • Common in ball-and-socket joints • Example is when you move atlas around the dens of axis (shake your head “no”)

12. Types of Ordinary Body Movements Figure 6.13c

13. Types of Ordinary Body Movements • Abduction • Movement of a limb away from the midline • Adduction • Opposite of abduction • Movement of a limb toward the midline

14. Types of Ordinary Body Movements Figure 6.13d

15. Types of Ordinary Body Movements • Circumduction • Combination of flexion, extension, abduction, and adduction • Common in ball-and-socket joints

16. Types of Ordinary Body Movements Figure 6.13d

17. Special Movements • Dorsiflexion • Lifting the foot so that the superior surface approaches the shin • Plantar flexion • Depressing the foot (pointing the toes)

18. Special Movements Figure 6.13e

19. Special Movements • Inversion • Turn sole of foot medially • Eversion • Turn sole of foot laterally

20. Special Movements Figure 6.13f

21. Special Movements • Supination • Forearm rotates laterally so palm faces anteriorly • Pronation • Forearm rotates medially so palm faces posteriorly

22. Special Movements Figure 6.13g

23. Special Movements • Opposition • Move thumb to touch the tips of other fingers on the same hand

24. Special Movements Figure 6.13h

25. Types of Muscles • Prime mover—muscle with the major responsibility for a certain movement • Antagonist—muscle that opposes or reverses a prime mover • Synergist—muscle that aids a prime mover in a movement and helps prevent rotation • Fixator—stabilizes the origin of a prime mover

26. Types of Muscles

27. Naming Skeletal Muscles • By direction of muscle fibers • Example: Rectus (straight) • By relative size of the muscle • Example: Maximus (largest)

28. Naming Skeletal Muscles • By location of the muscle • Example: Temporalis (temporal bone) • By number of origins • Example: Triceps (three heads)

29. Naming Skeletal Muscles • By location of the muscle’s origin and insertion • Example: Sterno (on the sternum) • By shape of the muscle • Example: Deltoid (triangular) • By action of the muscle • Example: Flexor and extensor (flexes or extends a bone)

30. Arrangement of Fascicles Figure 6.14

31. Agenda 3/28/12---Day 3 • Take out worksheet from yesterday • Go over • Facial muscles Con’t • Using facial muscles activity

32. Head and Neck Muscles • Facial muscles • Frontalis—raises eyebrows • Orbicularis oculi—closes eyes, squints, blinks, winks • Orbicularis oris—closes mouth and protrudes the lips • Buccinator—flattens the cheek, chews • Zygomaticus—raises corners of the mouth • Chewing muscles • Masseter—closes the jaw and elevates mandible • Temporalis—synergist of the masseter, closes jaw

33. Head and Neck Muscles • Neck muscles • Platysma—pulls the corners of the mouth inferiorly • Sternocleidomastoid—flexes the neck, rotates the head

34. Collins I2 lines • What is your favorite facial muscle? Why?

35. Agenda4/11/12---Day 1 • Finish Poster (10 minutes) • Notes on trunk muscles • Using book, label AND color muscles of the trunk • You MUST color • Label only the ones with color key next to it • Check to see if labeled correctly before you color

36. Head and Neck Muscles Figure 6.15

37. Muscles of the Trunk • Anterior muscles of the trunk • Pectoralis major—abducts and flexes the humerus • Intercostal muscles • External intercostals—raise rib cage during inhalation • Internal intercostals—depress the rib cage to move air out of the lungs when you exhale forcibly

38. Anterior Muscles of Trunk, Shoulder, Arm Figure 6.16a

39. Muscles of the abdominal girdle • Rectus abdominis—flexes vertebral column and compresses abdominal contents (defecation, childbirth, forced breathing) • External and internal obliques—flex vertebral column; rotate trunk and bend it laterally • Transversus abdominis—compresses abdominal contents

40. Anterior Muscles of Trunk, Shoulder, Arm Figure 6.16b

41. Posterior muscles of the trunk • Trapezius—elevates, depresses, adducts, and stabilizes the scapula • Latissimus dorsi—extends and adducts the humerus • Erector spinae—back extension • Quadratus lumborum—flexes the spine laterally • Deltoid—arm abduction

42. Muscles of Posterior Neck, Trunk, Arm Figure 6.17a

43. Muscles of Posterior Neck, Trunk, Arm Figure 6.17b

44. Collins I2 lines • Describe two trunk muscles in terms of location and the type of movement the muscle is responsible for

45. Agenda4/12/12---Day 2 • Discuss Collins • Complete trunk diagram • Answer questions # 19 & 20 • Label and color diagrams 6-7 & 6-8 • Notes on arm muscles

46. Muscles of the Upper Limb • Biceps brachii—supinates forearm, flexes elbow • Brachialis—elbow flexion • Brachioradialis—weak muscle • Triceps brachii—elbow extension (antagonist to biceps brachii)

47. Anterior Muscles of Trunk, Shoulder, Arm Figure 6.16a

48. Muscles of Posterior Neck, Trunk, Arm Figure 6.17a

49. Do Now4/16/12---Day 4 • Get out diagram packet

50. Agenda4/16/12---Day 4 • Finish diagrams • Go over diagrams • Finish notes • Diagram test is THIS friday