unit 3 b Flashcards
body movement
skeletal muscle attached to bone
muscle tone
-continuous and passive partial contraction of muscles
-maintain posture and balance
propel body fluids
constriction of organs and vessels by smooth muscle
heartbeat
cardiac muscles contract to produce heartbeat
Body heat
-contraction of skeletal muscle is important source of heat for body
-lot of energy produced from cellular respiration is lost as heat
Cardiac muscle
-found only in heart, generates heart bear
-under involuntary control
smooth muscle
-lines body cavities to propel fluids and food
-under involuntary control
skeletal muscle
-attaches to skeleton and enables body movement
-under conscious control
-compsoed of striated tissue with many nuclei
-muscles act only by pulling
cardiac muscle cells
-found only in heart
-consist of branching straited cels that interconnect
-intercalated discs separate adjacent cells
-part of cardiovascular system
smooth muscle cells
-elongated with tapered ends, lack striations, undeveloped sarcoplasmic reticulum
-thick and thin filaments
-part of whichever organ system they are in
Origin and insertions
Origins: less movable attachment of skeletal muscle
Insertion: more movable attachment of skeletal muscle
Example: Biceps brachii(both heads attach to portions of scapula)
movements and interactions of skeletal muscles
-function in groups
-muscle that causes action, and does majority of work is AGONIST
-muscles that oppose an action are ANTAGONISTS
-muscles that assist the prime mover are SYNERGISTS
major locations
Skeletal: skeletal muscles
Smooth: walls of hollow viscera, blood vessels
Cardiac: Wall of heart
Major function
Skeletal:Movement of bones at joints, maintenance of posture
Smooth: movement of viscera, peristalsis
Cardiac: pumping action of heart
Striations
Skeletal :present
Smooth: absent
Cardiac: present
