MUSCULOSKELETAL SYSTEM Muscles TYPES Skeletal forms the muscles

MUSCULOSKELETAL SYSTEM Muscles

TYPES Skeletal – forms the muscles attached to the skeleton - move the limbs and other body parts - long striated - subject to voluntary control - make up the muscular system

TYPES Smooth - spindle shaped and arranged in opposing layers - located in the walls of hollow organs -When they contract substances ( ex…) are moved along the pathways -involuntary

TYPES – CONT’D Cardiac muscles - striated, branching cells - fit closely together in spiral bundles in the heart - contraction pumps blood through the vessels - involuntary

- sole function of muscle tissue is to contract or shorten. - contraction causes movement - maintains posture - stabilizes joints - and generates heat.

All skeletal muscle cells are stimulated by motor neurons - most skeletal muscle contractions are smooth and sustained because rapid nerve impulses are reaching the muscle and the muscle cannot relax completely between contractions - strength of muscle contraction reflects number of cells contracting ( more = stronger)

ATP is the source of energy for muscle contraction - ATP stored in the muscles is used up with in seconds of activity - must continually be restored.

FAST TWITCH MUSCLE FIBRES -Contract quickly, get tired quickly

SLOW TWITCH MUSCLE FIBRES - contract slowly but last longer - “Dark Meat” -

TENDONS Dense fiborous tissue that attaches muscle to bone.