Flashcards in Ms lectures 5-6 Deck (13):
The ______ is the smallest functional contractile unit in a muscle.
What is the length of the micron and how many are end to end in a myofibril?
2.7 microns in length; 10,000 sarcomeres end to end in a myofibril.
The two contractile proteins are...
actin and myosin
The two regulatory proteins...
troponin and tropomyosin
True or False. Tropomyosin consists of two intertwined molecules about the length of seven actin molecules.
True or False. 300-400 globular actins in each of the two intertwined strands.
What is the function?
Troponin A: Inhibition/resting state in which it binds to actin, and not at the myosin binding site
Troponin C: binds calcium --> conformational change in troponin that allows movement of tropomyosin
Troponin T: binds to tropomyosin.
The two structural proteins are...
titin and nebulin
wide dark band of thick filaments in the middle of the sarcomere which overlap with the thin filaments
light band which lives between the ends of the A band consist of the ends of the thin filament that does not overlap the thick filament;
basically LIGHT and ACTIN
bisects the I band and consists of thin filaments from two sarcomeres
space between the opposing ends of the two sets of thin filaments; MYOSIN only.