Question

If the apical parts of the negative geotropic roots of mangrove plant are pasted with wax, which function of these roots will be affected?

• A. Exchange of $O_2$ and $C{O}_2$
• B. Water absorption
• C. Fixation of plant
• D. Photosynthesis

Answer 1

Answer: (A)

Exchange of $O_2$ and $C{O}_2$

Negatively geotropic roots of mangrove plants serve the purpose of the exchange of oxygen and carbon dioxide. These are otherwise called as breathing roots or pneumatophores. Some lateral roots of mangroves become specialised as pneumatophores in saline mudflats, pneumatophores are lateral roots that grow upward (negative geotropism) for varying distances and function as the site of oxygen intake.

So, the correct answer is option A.