BIOL 201 Lecture 14: Myosin & Muscle
Document Summary
Motor proteins are responsible for converting chemical energy like atp into mechanical work. Myosin can translocate actin filaments across a glass slide. Myosin ii forms bundles that pull the filaments inward causing the muscle cell to shorten/contract. Muscles are made of billions of contractile bundles of muscle fibers. Within each muscle fiber, there is a multinucleated muscle cell. Myoblasts fuse together to form one long multinucleated cell. Within a cross section of each multinucleated cell, there are a large number of myofibrils. Within each myofibril, you have a structure known as a sarcomere. The defining boundaries of a sarcomere are known as z disk. Myosin filaments located within the dark region (thick filaments) & actin filaments rils. nts. Myosin filaments located within the dark region (thick filaments) & actin filaments are in the light region (thin filaments). Are the basic unit of the sliding filament theory. When a muscle is stretched, z disks would be the furthest apart.