Musculoskeletal+period+1


 * Major Functions**
 * Body Movement**- Contraction of skeletal muscles is responsible for all of the movement in the body.
 * Maintenance of Posture**- Skeletal muscles contantly maintain how you can sit up or standing correctly
 * Respiration**- Muscels of the throat
 * Production of body Heat**- When the skeletal muscles contract and heat is given off as body heat
 * Communication**- Skeletal muscles are used for all communication like speaking, writing, typing, and even facial expressions.
 * Constrction of Organs and Vessels**- The cntraction of smooth muscles within the walls of internal organs and vessels. This helps propel and mix food and water in digestive track.
 * Heart Beat**- the contraction f caridac muscles causes the heart to beat.

These cells are pretty big. they have mutlinucli which is perfect for a muscle cell because it makes a lot of protein which a muscle needs to be big and strong. It has a lot of straits which help extend and contract the muscles. Cell shape- long, clindrical Nucleus- Multiple Function- Move the whole body Control-Voluntary || __**Function**__ **__Location__** 40% of body weight Contractility- shortens muscle with force, Excitability- responds to stimuli Extensibility- Skeletal mucsles can be stretched, Elasticity- Rcoil to orginal- resting length after stretch. ||  || All muscles in the body attached to bones || Cell- Spindle-shaped Nucleus- Single Function- Compression of organs, ducts, tube, etc Control Involuntary || Cells are small, spidle shaped usualy ||  || Walls of hollow organs blood vessels and glands || Cell- Branched Long Cells, striated branching, Actin myosin Heart myotilaments Nucleus- Single, central Control- Involuntary || Lung cells, striated, branching, Actin and myosin myofilaments ||  || Heart ||
 * Functions and locations of muscles**
 * __**Skeletal**__
 * **__Smooth__**
 * __**Cardiac**__

__**Tendons and Ligaments**__ Tendons are attachment points where the muscles are connected to the bone. Liggaments are tough connection tissue to and usually connecting bone to bone.

__**Bone Marrow**__ It is the soft tissue in the medullary cavity of the bone There are two types of Bone Marrow- Yellow bone marrow consists of fat, to be used for energy Red Bone Marrow has blood forming cells, to produce blood cells.

Osteoarthritis- results from the gradual wear and tear of the cartlidge between the joints that occurs with advancing age. 85% of people over 70 have it. Most commonly in Knees and hips in overweight individuals.

__**Osteoarthritis**__ media type="youtube" key="0dUSmaev5b0" height="349" width="425"

__**Facts**__
 * Over 30 facial muscles
 * Eye muscles are busiest muscles and move over 100,000 times.
 * Strongest muscle is your tongue
 * 72 muscles to produce speech.