Notecard 39-40

Skeletal muscle tissue

under voluntary control, move body by pulling on bones (walking, dancing, eating, or playing the piano)

cardiac muscle tissue

involuntary and found in the heart, when it contracts, blood is pumped through the blood vessels

smooth muscle tissue

involuntary found in the walls of hollow organs, in digestive tract it moves fluids and solids, as a lining in small arteries, it regulates vessel diameter

1. produce skeletal movement
2. maintain posture and body position
3. support soft tissues
4. guard body entrance and exits
5. maintain body temperature
6. provide nutrient reserves

functions of muscle tissue

produce skeletal movemtn

skeletal muscle contactions pull on tendons and move the bones(extending the arm, breathing swimming)

maintain posture and body position

tension in skeletal muscles stabilizes joints to help maintain body posture (holding head still)

support soft tissues

the abdominal wall and floor of the pelvic cavity consists of layers of skeletal muscle. Muscles support the weight of visceral organs and sheild internal tissues from injury

guard body entrances and exits

skeletal muscles encircle the openings of the digestive and urinary tracts (voluntary control of swallowing)

maintain body temperature

muscle contractions require energy; whenever energy is used, some heat is produces

provide nutrient reserves

the contractile proteins in skeletal muscles are broken down into amino acids, released into the circulation, some amino acids can be used by the liver to synthesize gluscose; can be broken down for energy

tendon

a bundle of collagen fibers of connective tissue layers (attaches the muscle to bone)

aponeurosis

broad sheet; provides attachment over a brad area that may involve more than one bone

epimysium

a dense layer of collagen fibers, surrounds the entire muscle

perimysium

fibrous layer that divides the skeletal muscle into a series of compartments

endomysium

thin layer of arcolar connective tissue that surround each muscle fiber

skeletal muscle

complex organ containing skeletal muscle fibers, connective tissues, blood vessels and nerves

muscle fascicle

bundle of muscle fibers

muscle fiber

sheathed in a delicate endomysium that contains capillaries, myosatellite cells, and axions of neurons

myosatellite cells

stem cells that function in the repair of damaged tissue

myoblast

groups of embryonic cells

sarcolemma

plasma membrane

sarcoplasm

cytoplasm; consists of myofibrils