Question

Velamen found in epiphytic roots is meant for

• A. Absorption of water from host
• B. Absorption of water from air
• C. Perennation
• D. Protection

Answer 1

The correct option is B Absorption of water from air

Velamen is a spongy, multiple epidermis that covers the roots of some epiphytic or semi epiphytic plants, such as orchid and Clivia species. The velamen of an orchid is the white or gray covering of aerial roots. It is many cell layers thick and capable of absorbing atmospheric moisture and nutrients. Often, the roots of orchids are associated with symbiotic fungi or bacteria. The latter may fix nutrients from the air. This functionality allows the orchid to exist in locations that provide a reproductive or vegetative advantage such as improved exposure or reduced competition from other plant species. The velamen also serves a mechanical function, protecting the vascular tissues in the root cortex, shielding the root from transpirational water loss and in many cases, adhering the plant to the substrate. So, velamen found in epiphytic roots is meant for absorption of water from air and not for absorption of water from host, perennation or protection.
Thus, the correct answer is option B.