Question

Which one of the following compounds inhibits the polymerization of tubulin to microtubules in animal cells?

• A. ATP
• B. Taxol
• C. Thymosin
• D. Vinblastine

Answer 1

The Correct Option is D

The question asks about a compound that inhibits the polymerization of tubulin to microtubules. Let's analyze each given option to determine the correct answer:

1. ATP: Adenosine triphosphate (ATP) is an energy-carrying molecule found in the cells of all living things. It does not inhibit tubulin polymerization. Rather, it provides energy for numerous cellular processes.
2. Taxol: Taxol, known as paclitaxel, is a microtubule-stabilizing agent. It binds to microtubules and prevents their disassembly, leading to cell cycle arrest at the mitotic phase. This behavior is opposite to inhibiting polymerization.
3. Thymosin: Thymosin is a thymic hormone involved in the modulation of the immune system. It doesn't interact with the polymerization of tubulin.
4. Vinblastine: Vinblastine is a well-known chemotherapeutic drug that inhibits the polymerization of tubulin into microtubules. It binds to tubulin dimers and prevents their assembly into microtubules, thereby disrupting the mitotic spindle during cell division.

Based on the above explanations, the compound that inhibits the polymerization of tubulin to microtubules in animal cells is Vinblastine. This mode of action makes Vinblastine effective in stopping rapidly dividing cancer cells.

Hence, the correct answer is Vinblastine.