1. © 2012 Pearson Education, Inc. 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

2. © 2012 Pearson Education, Inc. Figure 6.14a Example: Pectoralis major (anterior view) (a) A muscle that crosses on the anterior side of a joint produces flexion*

3. © 2012 Pearson Education, Inc. Figure 6.14b Example: Latissimus dorsi (posterior view) (b) A muscle that crosses on the posterior side of a joint produces extension*

4. © 2012 Pearson Education, Inc. Figure 6.14c Example: Medial deltoid (anterolateral view) (c) A muscle that crosses on the lateral side of a joint produces abduction

5. © 2012 Pearson Education, Inc. Figure 6.14d Example: Teres major (posterolateral view) (d) A muscle that crosses on the medial side of a joint produces adduction

6. © 2012 Pearson Education, Inc. Naming Skeletal Muscles By direction of muscle fibers Example: Rectus (straight) By relative size of the muscle Example: Maximus (largest)

7. © 2012 Pearson Education, Inc. Naming Skeletal Muscles By location of the muscle Example: Temporalis (temporal bone) By number of origins Example: Triceps (three heads)

8. © 2012 Pearson Education, Inc. 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)

9. © 2012 Pearson Education, Inc. Figure 6.15 (g) Unipennate (f) Bipennate Orbicularis oris Deltoid (d) Circular (a) Convergent Biceps brachii (a) (c) (b) Fusiform Sartorius (g) (c) Parallel (d) (e) Multipennate (e) (b) (f) Extensor digitorum longus Rectus femoris Pectoralis major

10. © 2012 Pearson Education, Inc. 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

11. © 2012 Pearson Education, Inc. Head and Neck Muscles Neck muscles Platysma—pulls the corners of the mouth inferiorly Sternocleidomastoid—flexes the neck, rotates the head

12. © 2012 Pearson Education, Inc. Figure 6.16 Cranial aponeurosis Orbicularis oris Orbicularis oculi Frontalis Zygomaticus Buccinator Platysma Temporalis Occipitalis Masseter Sternocleidomastoid Trapezius

13. © 2012 Pearson Education, Inc. Muscles of Trunk, Shoulder, Arm Anterior muscles Pectoralis major—adducts 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

14. © 2012 Pearson Education, Inc. Figure 6.17a Deltoid Sternum Pectoralis major Biceps brachii Brachialis Brachio- radialis Clavicle (a)

15. © 2012 Pearson Education, Inc. Muscles of Trunk, Shoulder, Arm Muscles of the abdominal girdle Rectus abdominis—flexes vertebral column and compresses abdominal contents (defecation, childbirth, forced breathing) External oblique—flex vertebral column; rotate trunk and bend it laterally Internal oblique—flex vertebral column; rotate trunk and bend it laterally Transversus abdominis—compresses abdominal contents

16. © 2012 Pearson Education, Inc. Figure 6.17b Pectoralis major Rectus abdominis Transversus abdominis Internal oblique External oblique Aponeurosis (b)

17. © 2012 Pearson Education, Inc. Muscles of Trunk, Shoulder, Arm Posterior muscles 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

18. © 2012 Pearson Education, Inc. Muscles of Trunk, Shoulder, Arm Muscles that arise from the shoulder girdle and cross the shoulder joint to insert into the humerus include: Pectoralis major Latissimus dorsi Deltoid PLAY A&P Flix™: Movement at the glenohumeral joint: An overview. PLAY A&P Flix™: Muscles that cross the glenohumeral joint. PLAY A&P Flix™: Muscles of the pectoral girdle. PLAY A&P Flix™: Muscles that act on the shoulder joint and humerus: An overview.

19. © 2012 Pearson Education, Inc. Figure 6.18a Olecranon process of ulna (deep to tendon) Triceps brachii Latissimus dorsi Occipital bone Sternocleidomastoid Trapezius Deltoid (a) Spine of scapula Deltoid (cut) Humerus

20. © 2012 Pearson Education, Inc. Figure 6.18b C7C7 T1T1 Erector spinae Iliocostalis Longissimus Spinalis Quadratus Iumborum (b)

21. © 2012 Pearson Education, Inc. Muscles of the Upper Limb Biceps brachii—supinates forearm, flexes elbow Brachialis—elbow flexion Brachioradialis—weak muscle; elbow flexion Triceps brachii—elbow extension (antagonist to biceps brachii) PLAY A&P Flix™: Movement at the elbow joint. PLAY A&P Flix™: Muscles of the elbow joint. PLAY A&P Flix™: The elbow joint and forearm: An overview.

22. © 2012 Pearson Education, Inc. Figure 6.17a Deltoid Sternum Pectoralis major Biceps brachii Brachialis Brachio- radialis Clavicle (a)

23. © 2012 Pearson Education, Inc. Figure 6.18a Olecranon process of ulna (deep to tendon) Triceps brachii Latissimus dorsi Occipital bone Sternocleidomastoid Trapezius Deltoid (a) Spine of scapula Deltoid (cut) Humerus

24. © 2012 Pearson Education, Inc. Muscles of the Upper Limb Muscles of the forearm, which insert on the hand bones and cause their movement include: Flexor carpi—wrist flexion Flexor digitorum—finger flexion Extensor carpi—wrist extension Extensor digitorum—finger extension PLAY A&P Flix™: Movements of the wrist and fingers (b). PLAY A&P Flix™: Movements of the wrist and fingers (a). PLAY A&P Flix™: Muscles that act on the wrist and fingers: An overview.

25. © 2012 Pearson Education, Inc. Muscles of the Lower Limb Muscles causing movement at the hip joint include: Gluteus maximus—hip extension Gluteus medius—hip abduction, steadies pelvis when walking Iliopsoas—hip flexion, keeps the upper body from falling backward when standing erect Adductor muscles—adduct the thighs PLAY A&P Flix™: Movement at the hip joint: An overview. PLAY A&P Flix™: Muscles that act on the hip joint and femur: An overview.

26. © 2012 Pearson Education, Inc. Figure 6.20a Gluteus medius Gluteus maximus Adductor magnus Iliotibial tract Biceps femoris Semitendinosus Semimembranosus Gastrocnemius (a) Hamstring group

27. © 2012 Pearson Education, Inc. Figure 6.20b Sciatic nerve Gluteus maximus Safe area in gluteus medius IIiac crest Posterior superior iliac spine (b)

28. © 2012 Pearson Education, Inc. Figure 6.20c 12th rib Iliac crest lliopsoas Psoas major lliacus Anterior superior iliac spine Sartorius Rectus femoris Vastus lateralis Vastus medialis Quadriceps Patellar ligament (c) Patella Adductor group 5th lumbar vertebra 12th thoracic vertebra

29. © 2012 Pearson Education, Inc. Muscles of the Lower Limb Muscles causing movement at the knee joint Hamstring group—thigh extension and knee flexion Biceps femoris Semimembranosus Semitendinosus

30. © 2012 Pearson Education, Inc. Figure 6.20a Gluteus medius Gluteus maximus Adductor magnus Iliotibial tract Biceps femoris Semitendinosus Semimembranosus Gastrocnemius (a) Hamstring group

31. © 2012 Pearson Education, Inc. Muscles of the Lower Limb Muscles causing movement at the knee joint Sartorius—flexes the thigh Quadriceps group—extends the knee Rectus femoris Vastus muscles (three) PLAY A&P Flix™: Muscles that cross the knee joint: An overview.

32. © 2012 Pearson Education, Inc. Figure 6.20c 12th rib Iliac crest lliopsoas Psoas major lliacus Anterior superior iliac spine Sartorius Rectus femoris Vastus lateralis Vastus medialis Quadriceps Patellar ligament (c) Patella Adductor group 5th lumbar vertebra 12th thoracic vertebra

33. © 2012 Pearson Education, Inc. Figure 6.20d Vastus lateralis (d) Sartorius Adductor muscles Inguinal ligament

34. © 2012 Pearson Education, Inc. Muscles of the Lower Limb Muscles causing movement at ankle and foot Tibialis anterior—dorsiflexion, foot inversion Extensor digitorum longus—toe extension and dorsiflexion of the foot Fibularis muscles—plantar flexion, foot eversion Soleus—plantar flexion PLAY A&P Flix™: Movements of the ankle and foot. PLAY A&P Flix™: Posterior muscles that act on the ankle and foot. PLAY A&P Flix™: Muscles that act on the ankle and foot: An overview.

35. © 2012 Pearson Education, Inc. Figure 6.21a Fibularis longus Fibularis tertius Tibialis anterior Extensor digitorum longus Tibia Soleus (a) Fibularis brevis

36. © 2012 Pearson Education, Inc. Figure 6.21b Gastrocnemius Soleus Calcaneal (Achilles) tendon Medial malleolus Lateral malleolus (b)

37. © 2012 Pearson Education, Inc. Figure 6.22 Facial Temporalis Masseter Shoulder Trapezius Deltoid Arm Triceps brachii Biceps brachii Brachialis Forearm Brachioradialis Flexor carpi radialis Pelvis/thigh lliopsoas Thigh (Quadriceps) Rectus femoris Vastus lateralis Vastus medialis Leg Fibularis longus Extensor digitorum longus Tibialis anterior Facial Frontalis Orbicularis oculi Zygomaticus Orbicularis oris Neck Platysma Sternocleidomastoid Thorax Pectoralis minor Pectoralis major Serratus anterior Intercostals Abdomen Rectus abdominis External oblique Internal oblique Transversus abdominis Thigh Sartorius Adductor muscle Gracilis Leg Gastrocnemius Soleus

38. © 2012 Pearson Education, Inc. Figure 6.23 Arm Triceps brachii Brachialis Forearm Brachioradialis Extensor carpi radialis longus Flexor carpi ulnaris Extensor carpi ulnaris Extensor digitorum lliotibial tract Leg Gastrocnemius Soleus Fibularis longus Calcaneal (Achilles) tendon Neck Occipitalis Sternocleidomastoid Trapezius Shoulder/Back Deltoid Latissimus dorsi Hip Gluteus medius Gluteus maximus Thigh Adductor muscle Hamstrings: Biceps femoris Semitendinosus Semimembranosus

39. © 2012 Pearson Education, Inc. Figure 6.19 Deltoid muscle Humerus

40. © 2012 Pearson Education, Inc. Figure 6.20b Sciatic nerve Gluteus maximus Safe area in gluteus medius IIiac crest Posterior superior iliac spine (b)

41. © 2012 Pearson Education, Inc. Figure 6.20d Vastus lateralis (d) Sartorius Adductor muscles Inguinal ligament