REFER TO YOUR OUTLINE… • THERE ARE 27MAJOR MUSCLES THAT YOU MUST LEARN. Use your book to label your muscle man
Essential Question • What are the structures of the muscular system?
The Muscular System • Comprises nearly half our weight. • Over 650 muscles. • Each muscle is made up of hundreds or thousands of muscle fibers.
Muscle Fibers • Bundles of threadlike structures called myofibrils • Composed of: • Myosin • Actin • Form overlapping pattern called sarcomere muscle muscle fiber sarcolemma sarcomere functional unit of muscle movement
Structures of the muscular system Connective tissue • Tendons • Fascia Muscles • Skeletal • Smooth • Cardiac • Sphincter
Skeletal muscles • Attached to bone • Striated (striped) appearance • Voluntary • Multinucleated muscle cell bundles
Smooth muscles • Also known as visceral muscles • Involuntary • Located in walls of digestive system, uterus & blood vessels
Cardiac muscle • Found only in the heart • Striated, branched • Involuntary • Cells are fused- when one contracts, they all contract, creating a synchronized heartbeat.
Sphincter muscles • Also called dilator muscles • Special, circular muscles • Located in the • digestive system • urinary system
Sphincter muscles are special circular muscles in the openings of our esophagus and stomach and small intestine, anus, urethra and mouth.
Structures of the muscular system There are 2 types of connective tissue that belong to the muscular system: • Tendons • Fascia
Tendons dense bands that connect skeletal muscle to the bone
Fascia Fibrous sheets of connective tissue that wrap around muscle bundles
How do skeletal muscles get their names? • Location • Size • Direction • Number of origins • However, • not all muscles are named by the above methods!
The muscular system reviewAnterior view 1.04 Remember the structures of the muscular system
The muscular system reviewPosterior view 1.04 Remember the structures of the muscular system
1.04 Remember the structures of the muscular systemEssential Question • What are the structures of the muscular system? 1.04 Remember the structures of the muscular system