Unit 4 Notes: Muscle Parts
(1) Types of Muscle Skeletal Cardiac Smooth
Cardiac Muscle Skeletal Muscle Smooth Muscle
(2) Skeletal Muscle Type of Movement: Location: Voluntary Allows overall body mobility Contracts fast w/great force, tires fast also Location: On top of bones & connecting them
(3) Cardiac Muscle Types of Movement: Location: Involuntary Steady, consistent movement Heartbeat (rate gauged by nervous system) Location: heart
(4) Smooth Muscle Type of Movement: Location: Involuntary Slower, yet consistent movement Forces fluids & solids through channels Location: Digestive & excretive organs Respiratory passageways
(5) Muscle Function Produce movement Maintain posture Stabilize joints Bones = attachment points Internal organs (move nutrients, waste, etc.) Maintain posture Unique to Bipedalism Stabilize joints Allows for wider range of movement and use of force Generate heat During contraction
(6) Levels of Organization Muscle (whole organ) Fascicle (portion of muscle) Muscle Fiber (single muscle cell) Myofibril (muscle cell organelle) Sarcomere (portion of myofibril) Myofilaments—Actin + Myosin (part of sarcomere) Macroscopic Microscopic
Thick Filament (myosin) Fascicle Muscle (organ) Muscle Fiber (cell) Myofibril Muscle Fiber (with many nuclei) Sarcomere Thin Filament (actin) Thick Filament (myosin)