The thick filament is composed of the myosin molecule. The thin filament is composed of the actin molecule. Flexing the head of myosin provides the powerstroke.
Myosin
actin and myosin
Most myosin molecules are composed of both a head and a tail domain.
Thick Filaments
Actin. Myosin are the thin ones.... it's actually the reverseThe thin filaments are composed primarily by the protein Actin.The thick filaments are composed primarily of the protein Myosin.
thick filaments
Sarcomeres are composed of actin (thin filaments) and myosin (thick filaments).
Myofibril, composed of actin and myosin.
sarcomere
Actin and myosin
Myosin makes up the THICK filaments, and actin makes up the thin filaments of myofibrils.