Muscular System Note Study

Functions, Organization, & The Sarcomere

The five functions of the muscular system

Describe the organization of a skeletal muscle from largest structure to smallest

Describe the sarcomere, including the structure of the two myofilaments

II. Function of Muscles (STUDY THIS AS IT’S IMPORTANT)

1. Support the body

2. Allow movement by making bones and other body parts move

3. Maintain body temperature

4. Assist movement of Cardiovascular and lymph

5. Protect internal organs and stabilize joints

Largest to smallest

Muscle belly - Fascicle - Muscle Fiber - Sarcomere → Myofibrils → Myofilament → Myosin & Actin

Sarcomere - Contractile unit of a muscle fiber

Organization:

Thich filaments - Myosin protein

Thin filaments - Actin protein

Myosin & Overlap in the sarcomere

Myosin filaments have extensions that grab onto actin forming a “CROSS BRIDGE”

Muscles Of The Head

Obicularis Oculi & Orbicularis Oris - “Orbit” which is like circles, Oculi think of that VR “Occulus” meaning Eye, Oris, think of the mouth, “Oral”