Final answer:
Microfilaments, or actin filaments, are thin components of the cytoskeleton that are composed of actin monomers. They are involved in cellular movement, such as muscle contraction, and can change the shape of a cell.
Step-by-step explanation:
Microfilaments, also known as actin filaments, are the thinnest component of the cytoskeleton. They are composed of two intertwined strands of actin monomers. Microfilaments have a structure that allows for the addition of new actin monomers at one end and disassembly at the other end, making them dynamic and capable of changing the shape of a cell. Their main function is in cellular movement, such as muscle contraction. Motor proteins, like myosin, interact with actin to generate a force that deforms the plasma membrane and changes the shape of the cell.