Chapter 6 The Muscular System Essentials of Human Anatomy & Physiology Seventh Edition Elaine N. Marieb Chapter 6 The Muscular System Slides 6.32 – 6.44 Lecture Slides in PowerPoint by Jerry L. Cook Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Types of Ordinary Body Movements 1. Flexion – decrease in angle of joint, brings bones closer together. Ex. Hinge Joint 2. Extension – Increase angle of joint, bring bones farther apart . . .Can have hyperextension = > 180 degrees 3. Rotation 4. Abduction – Moving limb away from midline 5. Adduction – Moving limb closer to midline 6. Circumduction – combo of flexion, extension, abduction, and adduction. Seen in ball and socket joints like the shoulder: proximal end is stationery, yet distal end can move in a circle and make a cone shape. Slide 6.32 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Body Movements Figure 6.13 Slide 6.33 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Special Movements 1. Dorsifelxion – up movement of foot 2. Plantar flexion – down movement of foot 3. Inversion – turn sole of foot medial 4. Eversion – turn sole of foot laterally 5. Supination – movement around radius and ulna  “turning backward”, radius and ulna are parallel 6. Pronation  “turning foreward”, radius rotates over ulna. 7. Opposition – movement of thumb when touch tips of other fingers on same hand Slide 6.34

Types of Muscles  muscles cannot push, can only pull Types of Muscles  muscles cannot push, can only pull. So most body movements are a result of muscles acting against eachother 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 Slide 6.35 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Naming of Skeletal Muscles Direction of muscle fibers Example: rectus (straight) Relative size of the muscle Example: maximus (largest) Slide 6.36a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Naming of Skeletal Muscles Location of the muscle Example: many muscles are named for bones (e.g., temporalis) Number of origins Example: triceps (three heads) Slide 6.36b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Naming of Skeletal Muscles Location of the muscles origin and insertion Example: sterno (on the sternum) Shape of the muscle Example: deltoid (triangular) Action of the muscle Example: flexor and extensor (flexes or extends a bone) Slide 6.37 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Head and Neck Muscles Figure 6.14 Slide 6.38 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Trunk Muscles Figure 6.15 Slide 6.39 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Deep Trunk and Arm Muscles Figure 6.16 Slide 6.40 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Muscles of the Pelvis, Hip, and Thigh Figure 6.18c Slide 6.41 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Muscles of the Lower Leg Figure 6.19 Slide 6.42 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Superficial Muscles: Anterior Figure 6.20 Slide 6.43 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Superficial Muscles: Posterior Figure 6.21 Slide 6.44 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings