5.3 Protein Interactions Modulated by Chemical Energy: Actin, Myosin, and Molecular Motors

myosin

this is a protein in muscle that has 2 heavy chains and 4 light chains that forma. left handed coil

thick filaments

these are rod like structured within aggregated myosin

actin

this is a protein in muscle that forms a long polymer

thin filaments

this is the name for actin, troponin, and tropomyosin

sarcomere

this is the name for one contractile unit

A band

this part of the sarcomere stretches the length of the thick filament

I band

this part of the sarcomere contains only thin filaments

Z disk

this part of the sarcomere is the attachment site of thin filaments

M line

this part of the sarcomere bisects the A band

tropomyosin

this protein binds to thin filament and blocks attachment site for myosin

troponin

this protein is a Ca2+ binding protein that causes tropomyosin to expose myosin binding site

subunit C

this part of troponin binds to Ca2+

Subunit I

this part of troponin prevents the binding of the myosin head to actin

subunit T

this part of the troponin links the troponin complex to tropomyosin

decrease

a ______ in ca2+ levels causes muscle relaxation