Muscular System

Muscular System
Functions
- movement
- control passages
- heat production
- communication
- stability
Structures
- 1 muscle
- Perimysium
- Fascicle
- epimysium
- fascia grades into
- bundles of fibres
- 1 fibre
- myofibril
- myofilaments
- myosin
- actin
Endomysium
Muscle Types
- Skeletal
- Attach to bones
- Heart muscle
- Cardiac
- Smooth
- Inside organs and blood vessels.
Cause dilation and constriction
Muscle Contraction
- Actin and myosin form crossbridges and
use ATP to perform powerstrokes and
shorten the sarcomere
- Sarcomere
- Contractile unit of a muscle. They lie end to end in Myofibrils.
- Myofibrils are composed of two myofilaments
Structures
- Myosin
Actin
15