GENERAL HISTOLOGY

Detailed explanation-1: -Myosin. Thick myofilaments are comprised of around 300 spirally arranged protein molecules called myosin. Each myosin molecule is composed of two heavy chains and four light chains.

Detailed explanation-2: -An individual sarcomere contains many parallel actin (thin) and myosin (thick) filaments. The interaction of myosin and actin proteins is at the core of our current understanding of sarcomere shortening.

Detailed explanation-3: -The fundamental functional unit of muscle is called a sarcomere. One muscle may contain as many as 100, 000 of the repeating sarcomere units. In the sarcomere, the myofilaments (thick filaments and thin filaments) are organized into parallel units.

Detailed explanation-4: -Thin filaments (actin) and thick filaments (myosin) are present in almost every cell type. Thin filaments, also called microfilaments, are 5 to 8 nm in diameter.