Which class of cytoskeletal fibres is made of solid rods of globular protein called actin?

Microfilaments are the class of cytoskeletal fibers composed of solid rods made of globular protein called actin. Actin is a critical protein that plays key roles in various cellular processes, including cell shape, motility, and division. Microfilaments are the smallest components of the cytoskeleton and are involved in supporting the cell's structure as well as enabling movement through contraction and extension.

The structure of microfilaments—being thin and flexible—allows them to form a dense network beneath the plasma membrane, which contributes to the cell's overall shape and mechanical support. Their ability to dynamically assemble and disassemble enables cells to respond quickly to environmental changes, facilitating processes such as muscle contraction in animal cells and cytoplasmic streaming in plant cells.

Understanding the characteristics and functions of microfilaments is essential in cell biology, as they provide insight into how cells maintain their structure and perform essential functions.