MUSCULAR SYSTEMTHE SYSTEM THAT ENABLES US TO MOVE, MAINTAINS OUR POSTURE AND HELPS IN HEAT PRODUCTION.

DID YOU KNOW?

•The longest muscle is the SARTORIUS.

•The biggest muscle is the GLUTEUS MAXIMUS.

•The smallest muscle is the STAPEDIUS.

•Our body is composed of 640 muscles.

FUNCTIONS OF THE MUSCLES

•Movement

•Heat production

•Posture

•protection

CHARACTERISTICS OF MUSCLES

•Contractility – the ability of muscles to shorten

•Elasticity – the ability of muscles to go back to its original shape

•Excitability – the ability of muscles to respond to stimuli

•Extensibility – the ability of muscle to lengthen

•Sphincter – muscles that constrict openings

CLASSIFICATION OF MUSCLES

FUNCTIONALLY

•Voluntary – can be moved at will

• Involuntary – can’t be moved intentionally

STRUCTURALLY

• Striated – have stripes across the fibers

• Smooth – no striations

TYPES OF MUSCLES

•Cardiac muscles

•Skeletal muscle

•Visceral muscle

SMOOTH MUSCLES

•Fibers are thin and spindle shaped.

•No striations

•Single nuclei

•Involuntary

•Contracts slowly

CARDIAC MUSCLE

•Cells are branched and appear fused to one another

• Has striations

•Each cell has a central nucleus

• involuntary

SKELETAL MUSCLES

•Fibers are long and cylindrical

•Multi-nucleated

•Striated

•voluntary

Smooth muscle

Cardiac muscle

skeletal muscle

No striation Striated

Involuntary Voluntary

Esophagus, lungs,

stomach, intestine

Heart Biceps, triceps,

muscles that are attached

to bones

ENUMERATION

•1-4. Give two (2) pairs of muscle movements.

•5-7. What are the three (3) kinds of muscle?

•8-10. Give three (3) functions of the muscular system.

ASSIGNMENT

•What are the three (3)parts of a muscle?

•How many percent of our body is composed of muscle?