Download Muscle

Muscle
3 Types of muscle
 Smooth- line the walls of internal organs and blood
vessels. Involuntary movement.
 Skeletal- striated, allow for movement, voluntary
control
 Cardiac- makes up the heart, striated, involuntary
SMOOTH
SKELETAL
CARDIAC
How do muscles work?
 By relaxing and contracting in pairs- when biceps
contract, triceps relax. Called opposable pairs
SLIDING FILAMENT THEORY
 Muscle fibers are made of 2 different filaments-
ACTIN AND MYOSIN
They are arranged in units called sarcomeres.
The actin filaments surround the myosin filament. When the
muscle contracts, the actin ends slide over each other and
the myosin in the middle thickens. (The myosin fibers form
cross bridges which grabs onto the actin filament and pull
it towards the middle of the sarcomere.)