Muscle Flashcards
What are the properties of skeletal muscle?
Contractility
Excitability
Extensibility
Elasticity
What are the three types of muscle?
Cardiac
Skeletal
Smooth
What is the sarcolemma?
Covering of the muscle
What is the sarcoplasm?
Cytoplasm of the muscle cells
What are myofibrils?
Contractile threads of the muscle cells
What is a sarcomere?
Structural unit of a myofibril consisting of a dark band and adjective light band (shortens)
What are the two myofilaments?
actin
myosin
What is the I band made up of?
thin actin (I is a THIN letter)
What is the H band made up of?
thick myosin (H is a THICK letter)
What is the M line?
Linked myosin filaments
What is the A band?
Where myosin and actin overlap
What myofilament has heads?
myosin
What does tropomyosin do?
reveals attachments sites when calcium binds to troponin
What does troponin do?
Calcium binds to it which causes it to move the tropomyosin it is attached to
How does myosin attach to actin?
Myosin heads are able to attach when calcium activates the troponin-tropomyosin complex that reveals attachment sites on the actin