1. Gross Anatomy of the Muscular System
Lab
Week of February 18, 2008
Marieb & Mitchell: Exercise 15
Martini: Chapter 11

2. Organization of Skeletal Muscle Fibers
fascicles
fibers
fibers of a single fascicle always parallel
fascicles of a muscle can be arranged in various ways

3. Muscles are classified by how the fascicles are organized
Parallel (e.g., biceps brachii muscle)
most common arrangement
Convergent (e.g.,pectoralis muscle)
fascicles fan or triangle shaped, converge to attach

4. Muscles are classified by how the fascicles are organized
Pennate (unipennate, bipennate and multipennate)
fasicles form angle toward tendon
Circular (e.g.,orbicularis oris)
sphincter, contracts to reduce diameter of opening

5. Origins and Insertions
The ends of skeletal muscles are always attached to other structures
fixed end is called ORIGIN
usually attached to bone or cartilage
movable end is called INSERTION
usually proximal to insertion

6. How are muscles named? location in the body Origin and Insertion
e.g., temporalis muscle
Origin and Insertion
first part = origin, 2nd part = insertion
Fascicle Organization
e.g., Rectus means “straight”
e.g., transverse means “across”
e.g., oblique means “oblique angle”

7. How are muscles named? Relative Position
e.g., superficialis, internus, lateralis, etc…
Structural Characteristics (shape and size)
e.g., deltoid, rhomboid, major, longus, etc…
Action
e.g., abductor, extensor, rotator, etc…

8. Muscular Actions Agonists (prime mover) Antagonist Synergists Fixators
responsible for a particular movement
Antagonist
against movement of agonist
Synergists
aid agonists, stabilize an action
Fixators
specialized synergists
immobilize the origin of agonist so all tension is exerted at the insertion point

9. Muscles of the Head and Neck
Epicranius
frontalis
action: raises eyebrows, wrinkles forehead

10. Muscles of the Head and Neck
Epicranius
occipitalis
action: tenses and pulls scalp posteriorly

11. Muscles of the Head and Neck
Orbicularis Oculi
action: closes eye, squinting

12. Muscles of the Head and Neck
Orbicularis oris
action: constricts mouth (whistle, kissing)

13. Muscles of the Head and Neck
Zygomaticus
action: the elevates corners of mouth and upper lip
smiling muscle
antagonist to depressor
anguli oris

14. Muscles of the Head and Neck
Levator Labii Superioris
action: raises upper lip, opens lips

15. Muscles of the Head and Neck
Depressor Labii Inferioris
action: depresses lower lip

16. Muscles of the Head and Neck
Depressor Anguli Oris
action: draws corners of mouth down
frowning muslce
antagonist to
zygomaticus

17. Muscles of the Head and Neck
Depressor Anguli Oris
action: draws corners of mouth down
frowning muslce
antagonist to
zygomaticus

18. Muscles of the Head and Neck
Masseter
origin: zygomatic arch
insertion: mandibular ramus
action:
elevates mandible
closes jaw

19. Muscles of the Head and Neck
Temporalis
action:
elevates mandible
closes jaw

20. Muscles of the Head and Neck
Sternocleidomastoid
origin: clavicle or manubrium
insertion: mastoid process
action:
together: flex neck
1 side: bends head
towards shoulder and
turns face to opposite
side

21. Muscles of the Head and Neck
Scalenes
origin: cervical vertebrae
insertion: Ribs 1-2
action: elevates ribs,
flexes neck

22. Muscles of the Head and Neck
Splenius Capitis
action: extend and hyperextend head

23. Muscles of the Trunk and Back
Erector Spinae
iliocostalis
spinalis
longissimus
together: extends vertebral column
along: lateral flexion

24. Muscles of the Trunk and Back
External Intercostals
origin: rib above
insertion: rib below
action: elevates ribs
inspiration

25. Muscles of the Trunk and Back
Internal Intercostals
origin: rib below
insertion: rib above
action: depresses ribs
breath out

26. Muscles of the Trunk and Back
Diaphragm
origin: xiphoid process,
cartilage of ribs 4-10, lumbar
vertebrae
action: expands thoracic cavity, compresses abdominopelvic cavity

27. Muscles of the Trunk and Back
Transverse Abdominus
insertion: linea alba
action: compresses abdominopelvic cavity

28. Muscles of the Trunk and Back
Internal Oblique
insertion: linea alba
action: compresses abdomen, depresses ribs, flexes or bends spine

29. Muscles of the Trunk and Back
External Oblique
insertion: linea alba
action: compresses abdomen, depresses ribs, flexes or bends spine

30. Muscles of the Trunk and Back
Rectus Abdominus
origin: pubic symphesis
insertion: xyphoid process
action: depresses ribs, compresses abdomen, flexes vertebral column

31. Muscles of the Trunk and Back
Trapezius
origin: midline of neck and back
insertion: clavicles and scapular spines
action: elevation, depression, rotation, adduction of scapula, extension of head

32. Muscles of the Trunk and Back
Rhomboid Major
origin: T2-T5 spinous processes
insertion: vertebral border of scapula
action: adduction of scapula

33. Muscles of the Trunk and Back
Rhomboid Minor
origin: C7 and T1 spinous process
insertion: vertebral border of scapula
action: adduction of scapula

34. Muscles of the Trunk and Back
Levator Scapulae
origin: C1-4 transverse process
insertion: vertebral border of scapula
action: elevates scapula

35. Muscles of the Trunk and Back
Pectoralis Minor
origin: anterior surface of ribs 3-5
insertion: coracoid process of scapula
action: depresses and contracts scapular end of clavicle (in complement with subclavius muscle)

36. Muscles of the Trunk and Back
Serratus Anterior
origin: ribs
insertion: scapula
action: abducts scapula, swings shoulder anteriorly

37. Gross Anatomy of the Muscular System
Lab
Week of February 25, 2008
Marieb & Mitchell: Exercise 15
Martini: Chapter 11
MUSCLES OF THE UPPER EXTREMITIES

38. Pectoralis Major Origin Insertion Action
Cartilages of ribs 2-6, body of sternum, inferior medial clavicle
Insertion
Humerus (greater tubercle and lip of intertubercular groove)
Action
Flex, adduct, medially rotate shoulder joint

39. Latissimus Dorsi Origin Insertion Action T6-12, lumbar, sacrum, ileum
Humerus (floor of intertubercular groove)
Action
Adduction, extension, medial rotation at the shoulder joint

40. Coracobrachialis Origin Insertion Action Coracoid process of scapula
Humerus (shaft)
Action
Adduct, flex at shoulder joint

41. Supraspinatus Origin Insertion Action Rotator cuff group
Supraspinous fossa of scapula
Insertion
Humerus (greater tubercle)
Action
Abduction at shoulder joint, stabilizes joint
Rotator cuff group

42. Infraspinatus Origin Insertion Action Rotator cuff group
Infraspinous fossa of scapula
Insertion
Humerus (greater tubercle)
Action
Lateral rotation at shoulder joint
Rotator cuff group

43. Teres Minor Origin Insertion Action Rotator cuff group
Lateral border of scapula
Insertion
Humerus (greater tubercle)
Action
Lateral rotation at shoulder joint, stabilizes
Rotator cuff group

44. Subscapularis Origin Insertion Action Rotator Cuff Group
Subscapular fossa of scapula
Insertion
Humerus (lesser tubercle)
Action
Medial rotation at shoulder joint
Rotator Cuff Group

45. Teres Major Origin Insertion Action Inferior angle of scapula
Humerus (lip of intertubercular groove)
Action
Extension, adduction, medial rotation at shoulder joint

46. Deltoid Origin Insertion Action Clavicle, scapula (spine and acromion)
Deltoid tuberosity of humerus
Action
Altogether  Abduction at shoulder joint
Anterior  flexion, medial rotation at shoulder
Posterior  extension, lateral rotation at shoulder

47. Biceps Brachii Origins Insertion Action Long head Short head
Supraglenoid tubercle of scapula
Short head
Coracoid process of scapula
Insertion
Tuberosity of radius
Action
Flex at elbow AND shoulder joint, supination

48. Brachialis Origin Insertion Action Humerus Ulna
Flexes forearm (elbow joint)

49. Triceps Brachii Origin Insertion Action
Long: Infraglenoid tubercle of scapula
Lateral: humerus
Medial: humerus
Insertion
Olecranon of Ulna (for all 3)
Action
Long: extension elbow joint, extension and adduction at shoulder joint
Lateral and Medial: extension at elbow joint

50. Brachioradialis Origin Insertion Action Distal humerus radius
Flexion at elbow joint

51. Pronator Teres
Action
Pronation (forearm)

52. Flexor Carpi Ulnaris
Action
Flex, adduct wrist

53. Flexor Carpi Radialis
Action
Flex, abduct wrist

54. Flexor Digitorum Superficialis
Action
Flexion at proximal interphalangeal
Flexion at metacarpophalangeal
Flexion at wrist

55. Extensor Carpi Radialis Longus
Action
Extend, abduct wrist

56. Extensor Carpi Radialis Brevis
Action
Extend, abduct wrist

57. Extensor Carpi Ulnaris
Action
Extend, adduct wrist

58. Extensor Digitorum
Action
Extension at finger joints and wrist joints

59. Adam Packet 1: muscles of the head, neck, chest and back
Using the Adam software, identify the muscles in the packet (pgs 8-16).
Answer questions 1-15 on a SEPARATE piece of notebook paper and turn it in by NEXT LAB PERIOD.
NOTE:
You will find the answers in Exercise 15 of Marieb and Chapter 11 of Martini.