OTOT

The Muscular System

Muscle System Functions

 

•       Provides voluntary movement of body

–      Enables breathing, blinking, and smiling

–      Allows you to hop, skip, jump, or do push-ups

•       Maintains posture

•       Produces heat

•       Causes heart beat

•       Directs circulation of blood

–      Regulates
 blood
pressure

–      Sends blood to different areas of the body

•       Provides movement of internal organs

–      Moves food through digestive tract

–      Enables bladder control

•       Causes involuntary actions

–      Reflex actions

–      Adjusts opening of pupils

–      Causes hair to stand.

Muscle Tissue Characteristics

•      Is made up of contractile fibers

•      Provides movement

•      Controlled by the nervous system

–     Voluntary- consciously controlled

–     Involuntary- not under conscious control

•      Examples:

     Skeletal, Smooth, Cardiac

  

Comparison of Muscle Types

Muscle Tissue Anatomy

Production of Energy for Muscle

•      ATP (adenosine triphosphate)

–     A type of chemical energy

–     Needed for sustained or repeated muscle contractions

•      Muscle cells must have three ways to store or make ATP

–     Creatine phosphate

•      Rapid production of energy

–     Aerobic respiration 

•      Uses body’s store of glucose

–     Lactic acid production

                               Small amounts of ATP

 

Mechanics of a Muscle Contraction

•      When each sarcomere becomes shorter it causes each myofibril to become shorter.

•      When each myofibril becomes shorter it causes the muscle fibers to become shorter

            When each muscle fiber shortens the overall muscle contracts.