{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

The areas of the a bands contain the heavier thick

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: f each thin myofilament is attached to the α-actinin in the Z line within the light areas called the I bands. The areas of the A bands contain the heavier thick filaments as well as thin filaments and are therefore denser and darker staining. Thin myofilaments are F-actin, with Ca2+-binding troponin and tropomyosin. The thick filaments are bundles of myosin. The end of each myosin contacts F-actin in the thin filaments. These interactions cause the filaments to slide past each other, shortening the sarcomeres (next 2 slides.) DIMERS. Interaction b/w THIN and THICK filaments (actin & myosin) slide against each other, thus shortening and causing a CONTRACTION. Sarcomere? Contractile region of muscle fiber.. Fig. 10-9 Fig. 10-11 Surface of muscle fiber (sarcolemma) has DEEP INVAGINATIONS which protrude down to the center of the fiber -surround all the fibrils in there!! These invaginations called T-TUBULES. T tubules are invaginations of the sarcolemma which coordinate Ca2+ release throughout the sarcoplasmic ret...
View Full Document

{[ snackBarMessage ]}

Ask a homework question - tutors are online