The cytoskeleton is composed of which components?

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Multiple Choice

The cytoskeleton is composed of which components?

The cytoskeleton is a dynamic network of protein filaments that gives the cell its shape, provides mechanical support, and serves as tracks for movement of organelles and cargo. It consists of three main filament systems: microfilaments, intermediate filaments, and microtubules. Microfilaments are thin strands made of actin and are key for changing cell shape and enabling movement. Intermediate filaments are more rope-like and provide mechanical strength to the cell. Microtubules are hollow tubes built from tubulin that organize the cell’s interior, position organelles, and form the mitotic spindle during cell division. These filaments continually assemble and disassemble, allowing quick remodeling as the cell’s needs change. The other options describe things that aren’t part of the cytoskeleton: genetic material and protein synthesis machinery (DNA, RNA, ribosomes); basic biomolecule classes (lipids, carbohydrates, proteins) that make up membranes and enzymes but aren’t the filament network; and whole organelles (chloroplasts, mitochondria, nuclei) rather than the filamentous framework inside the cell.

The cytoskeleton is a dynamic network of protein filaments that gives the cell its shape, provides mechanical support, and serves as tracks for movement of organelles and cargo. It consists of three main filament systems: microfilaments, intermediate filaments, and microtubules. Microfilaments are thin strands made of actin and are key for changing cell shape and enabling movement. Intermediate filaments are more rope-like and provide mechanical strength to the cell. Microtubules are hollow tubes built from tubulin that organize the cell’s interior, position organelles, and form the mitotic spindle during cell division. These filaments continually assemble and disassemble, allowing quick remodeling as the cell’s needs change.

The other options describe things that aren’t part of the cytoskeleton: genetic material and protein synthesis machinery (DNA, RNA, ribosomes); basic biomolecule classes (lipids, carbohydrates, proteins) that make up membranes and enzymes but aren’t the filament network; and whole organelles (chloroplasts, mitochondria, nuclei) rather than the filamentous framework inside the cell.

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