ANATOMY

Detailed explanation-1: -The thin filament contains several important contractile regulatory proteins (Figure 4). The main component is the actin filament, which is formed from the polymerization of globular actin molecules. Each globular actin monomer contains a binding site for the globular myosin head.

Detailed explanation-2: -Thin filament proteins The thin filaments contain three different proteins-actin, tropomyosin, and troponin. The latter is actually a complex of three proteins. Actin, which constitutes about 25 percent of the protein of myofilaments, is the major component of the thin filaments in muscle.

Detailed explanation-3: -The main proteins involved are myosin, actin, and titin. Myosin and actin are the contractile proteins and titin is an elastic protein. The myofilaments act together in muscle contraction, and in order of size are a thick one of mostly myosin, a thin one of mostly actin, and a very thin one of mostly titin.

Detailed explanation-4: -Thin myofilaments consists of actin, troponin and tropomyosin.

Detailed explanation-5: -Each sarcomere is composed of protein filaments (myofilaments) that include mainly the thick filaments called myosin, and thin filaments called actin. The bundles of myofilaments are called myofibrils.