1. Muscular System 600 Muscles

2. OBJECTIVES Key Objective Describe the structure of the muscle Be able to describe movement and maintenance of posture in terms of antagonistic muscle action. Understand the gross and microscopic structure of skeletal muscle, and the ultrastructure of a myofibril. Understand that muscles are effectors. Be able to describe the structure, location and general properties of slow and fast skeletal muscle fibres.

3. 3 types of muscles Smooth Muscles- Which include the muscles of internal organs and blood vessels. These muscles move involuntary. Smooth Muscles- Which include the muscles of internal organs and blood vessels. These muscles move involuntary. Cardiac Muscle- Found only in the heart and also involuntary. Cardiac Muscle- Found only in the heart and also involuntary. Skeletal Muscles- Are voluntary and help you move. Skeletal Muscles- Are voluntary and help you move.

4. Muscle Movement Involuntary- Automatically move without you knowing. Involuntary- Automatically move without you knowing. Voluntary- Brain sends message to muscle. You control the movements. Voluntary- Brain sends message to muscle. You control the movements.

5. Occuli Sternomastoid Pectoralis Major Bicep Brachii External Oblique Sartorius Extensor Digitorum Tibialis Anterior Quadriceps Abdominals Facial Buccinators

6. Types Of Muscles Smooth Muscle- Digestive organs, Makes up 7- 8% of your muscles. Smooth Muscle- Digestive organs, Makes up 7- 8% of your muscles. Involuntary Involuntary

7. Types of Muscles-skeletal Skeletal Muscles-muscles that move bones Skeletal Muscles-muscles that move bones Attached to bones by tendons Attached to bones by tendons Most numerous in the body Most numerous in the body Look striped or striated Look striped or striated Voluntary muscles Voluntary muscles Makes up 90% of your muscles Makes up 90% of your muscles

8. Types of Muscles-Smooth Muscles Smooth muscles- nonstriated Smooth muscles- nonstriated Involuntary Involuntary Move the internal organs Move the internal organs Contract and relax slowly Contract and relax slowly Makes up 7-8% of your muscles. Makes up 7-8% of your muscles. Example- small intestine Example- small intestine

9. Types of Muscles-Cardiac Muscle Cardiac muscle-found only in the heart Cardiac muscle-found only in the heart Involuntary Involuntary Striations Striations Makes up 3% of your muscles. Makes up 3% of your muscles. Contracts about 70 times a minute every day of your life. Contracts about 70 times a minute every day of your life. By age 70 heart contracts 2.5 billion times (assume resting heart beat). By age 70 heart contracts 2.5 billion times (assume resting heart beat).

10. Types of Injuries Strain- Muscle “pull” or “strain” Strain- Muscle “pull” or “strain” Tearing a muscle fiber(s), followed by bleeding or swelling of muscle Tearing a muscle fiber(s), followed by bleeding or swelling of muscle Muscle Cramp- Prolonged contraction of muscle, ion imbalance Muscle Cramp- Prolonged contraction of muscle, ion imbalance

11. Muscle Terms Flexion- Movement that reduces a joint angle Extension- A movement that increases a joint angle

12. Body Movements Flexing of the hamstring.

13. Body Movements cont. Extension of the quadriceps.

14. How Muscles Work Skeletal muscles-when one muscles contracts- another muscle relaxes Skeletal muscles-when one muscles contracts- another muscle relaxes Muscles always pull- never pushes Muscles always pull- never pushes Muscles use glucose Muscles use glucose Produce thermal energy when they contract Produce thermal energy when they contract Muscles that are not exercised become smaller Muscles that are not exercised become smaller How muscles work

15. Muscle Pairs Your muscles work in teams to move your body. An example of this is your Bicep and Tricep.

16. Trapezius Deltoid Tricep Latissimus Dorsi Gluteus Maximus Hamstring Gastrocnemius

18. Antagonistic muscle action

19. The Muscle

20. The Muscle Fibre

21. Myofibrils

22. Muscle filaments

23. Thick filaments

24. Thin filaments

25. Slow vs Fast Twitch muscles