Answer:
D. it takes millions of years to form
Yes they do without it they could not produce protein.
Answer:
The correct answer: C) allows the behavior of microtubules called dynamic instability.
Explanation:
Microtubules are structures that are part of the cytoskeleton and help provide structure and shape to eukaryotic cells, besides assisting in the transport of organelles and vesicles.
Microtubules are formed by the polymerization of a dimer of two tubulins.
Microtubules have the particularity of being able to easily assemble and disassemble, which enlarges and shrinks the microtubule respectively. This property of the microtubules is important to their functions and is called dynamic instability.
In order to achieve dynamic instability, tubulin dimers can bind two molecules of GTP - for polymerization to happen, one of the GTP molecules is hydrolyzed to catalyze the reaction, thus becoming GDP. In the same matter, the energy generated from the depolymerization with turn the GDP into GTP.
