Microtubules have an inner diameter of and an outer diameter of . Microtubules have an inner diameter of and an outer diameter of . 15 mm; 25 mm 8 nm; 12 nm 25 nm; 30 nm 15 nm; 25 nm 7 mm; 14 mm

C. 25 nm; 30 nm

Explanation:

Microtubules are tubulin polymers which form part of the cytoskeleton and provide the eukaryotic cells with structure and shape. A microtubule's outer diameter is 30 nm, and its inner diameter is 25 nm.

Microtubules are fibrous, hollow shafts whose principal function is to support and shape the cell. They often serve a role of transport, as they are the routes by which organelles travel through the cell.

Hence, the correct option is C.

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation: