What structure is composed of hollow rods made of tubulin proteins?

The structure composed of hollow rods made of tubulin proteins is known as microtubules. Microtubules are one of the three main components of the cytoskeleton in eukaryotic cells, alongside microfilaments and intermediate filaments. They play critical roles in various cellular functions, including maintaining cell shape, enabling cellular motility through structures like cilia and flagella, and facilitating cell division by forming the mitotic spindle.

The hollow nature of microtubules is significant because it allows them to resist compression and provides the necessary structural integrity to the cells. Additionally, they are dynamic structures that can rapidly grow and shrink, allowing cells to adapt to changing physiological situations swiftly.

While centrioles are made of microtubules and play a significant role in cell division as part of the centrosome, they are specific structures rather than general components. Microfilaments, on the other hand, are composed of actin and are involved in muscle contraction and cell movement, and intermediate filaments consist of various proteins that provide tensile strength to cells. Each of these structures has distinct characteristics and functions, highlighting the unique contribution of microtubules in the cell.