What exactly does the thick filament actually look like on the microscopic level? Well, basically the thick filament consists of a protein known as myosin. And many of these myosin proteins combine together and intertwine to basically form our thick filament. So these thick filaments basically wrap around one another, or these myosin wrap around one another to form our thick filament. And on the edges, at the end of each of these thick filaments, we basically have extensions known as myosin heads. And these myosin heads, as we'll see in the next lecture, are basically responsible for actually binding and interacting with our thin filaments.