1 / 16

Muscle Physiology: Structure, Contraction, and Force Production

Explore the macrostructure and microstructure of skeletal muscle, the sliding-filament theory of muscular contraction, fiber types, muscle action types, and the role of connective tissue. Learn how calcium and ATP contribute to myosin cross-bridge cycling and force production. Discover the factors affecting muscle force and the different arrangements of muscle fibers.

rosemarysmith
Download Presentation

Muscle Physiology: Structure, Contraction, and Force Production

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 1 C H A P T E R Muscle Physiology

  2. Chapter Outline Skeletal muscle macrostructure and microstructure Sliding-filament theory of muscular contraction Fiber types Types of muscle action Force production

  3. Three Types of Connective Tissue:Epimysium, Perimysium, and Endomysium

  4. A Motor Unit

  5. Sectional View of a Muscle Fiber

  6. Detailed View of Myosin and Actin Protein Filaments in Muscle

  7. The discharge of an action potential from a motor nerve signals the release of calcium from the sarcoplasmic reticulum into the myofibril, causing tension development in muscle.

  8. Contraction of a Myofibril: Stretched Muscle

  9. Contraction of a Myofibril: Partially Contracted Muscle

  10. Contraction of a Myofibril: Completely Contracted Muscle

  11. Calcium and ATP are necessary for myosin cross-bridge cycling with actin filaments.

  12. Type II, or fast-twitch, muscle fibers are capable of developing higher forces than Type I, or slow-twitch, muscle fibers—especially at higher velocities of muscle action.

  13. The number of cross-bridges that are attached to actin filaments at any instant in time dictates the force production of a muscle.

  14. Force-Velocity Curve for Eccentric and Concentric Actions

  15. Three Arrangements of Muscle Fibers Fibers parallel to tendon Bipennate muscle Unipennate muscle

  16. Many factors may affect rate of cross-bridge cycling and thus force, including neural activation, calcium concentration, myosin ATPase activity, preloading, prestretch, muscle fiber type and ultrastructure, fatigue through a variety of mechanisms, and number of contractile components (myosin and actin) in parallel.

More Related