Flashcards in Muscular System Deck (69)
Types of Muscle
Narrow cylindrical fibers, non-striated, uninucleate; occurs in walls of internal organs; is involuntary;
Has striated, branched, generally uninucleated fibers; occurs in walls of heart; is involuntary;
Has striated, tubular, multinucleated fibers; is usually attached to skeleton; is voluntary.
Functions of the Muscular System
Support the body
Allow for movement of bones and other structures
Help maintain constant body temperature
Assist in movement of fluids in cardiovascular and lymphatic vessels
Fluid filled sacs that provide cushioning between tendons and bones
The connective tissue that connects muscle to bone
Attachment of a muscle to a stationary bone
Attachment of a muscle on a bone that moves
Does most of the work when moving
Assists the prime mover
Works against the prime mover - purpose is to undo what was done by the prime mover
Muscles are named based on what seven characteristics?
Direction of fibers
Number of attachments
Do muscles pull or push?
Portion of sarcolemma that penetrates muscle cells.
Smooth endoplasmic reticulum that stores Ca+
One contracting unit of the muscle cell; made of the proteins actin and myosin
Thick filaments shaped like a golf club
Region on a sarcomere where actin but no myosin is
Region where myosin is but no actin
Length of the myosin fiber
How do filaments go over one another during muscle contraction?
Filaments slide over one another - do NOT crunch up!
First step of ATP in cellular work of motion...
ATP is split when myosin head is unattached (so becomes ADP)
Second step of ATP in cellular work of motion
ADP + P are bound to myosin as myosin head attaches to actin
Third step of ATP in cellular work of motion
Upon ADP+P release, power stroke occurs; head bends and pulls actin
Fourth step of ATP in cellular work of motion
Binding of fresh ATP causes myosin head to return to resting position