Muscular System
4 Properties of Muscles
- Excitability
- Contractibility
- Extensibility
- Elasticity
Functions of the Muscular System
- Maintaining posture
1. Spine(?)
- Supporting soft tissue
- Movement
1. Voluntary
2. involuntary
3. heart muscles
4. runnings
- Guarding entrances and exits of the body
1. Opening mouth
2. ‘Making a deposit
- Generate heat and maintain body temp
1. shivering
Types of Muscle Tissue
- Cardiac Muscle
* Characteristics
* Striated
* Involuntary movement
* Structure
* Proteins for striations (sarcerations)
* Thick = Actin
* Thin = Myiacyn
* Short, cylindrical-shaped, branched cells
* They break off from each other.
* Un-nucleated
* Fibers are formed to create a network
* Cells connect to each other at intercalated discs
* Connects the cells together.
* Location
* Makes up walls of the wall
* How do they work?
* Contract quickly and rhythmically. - Visceral (smooth) Muscle
* Characteristics
* Involuntarily contracted
* Non-striated
* Structure
* Flat, short, spindle-shaped cells
* Uni-nucleated
* Fibers are arranged to form sheets
* Location
* Lines internal organs, and vessels
* How do they work?
* Pull action = Peristalsis. - Skeletal Muscle
* Characteristics
* Striated
* Voluntarily controlled
* Attached to bones movement of fibrous tissue
* Structure
* Lond, cylindrical shaped cells
* Multinucleated
* Fibers are arranged to form bundles. Many bundles are in a Fascicle.
* Location
* Entire body
* How do they work?
* Contract quickly, but can’t stay contracted for long.
Muscle Movement
- Origin
* Start of muscle
* ^^Fixed^^ - Insertion
* End of the muscle
* The part that ^^actually moves^^ - Prime Mover
* Muscle that ^^creates^^ the action - Synergists
* Help the movement happen - Antagonist
* Muscle that ^^opposes^^ the action
Range of Motion
- Abduction
- Adduction
- Flexion
- Extension
- Elevation
- Depression
- Rotation
- Circumduction
- Supination
- Pronation
- Dorsiflexion
- Plantar Flexion