Question

Which of the following is an adaptation that enhances the uptake of water and minerals by roots?

(A) mycorrhizae

(B) pumping through plasmodesmata

(C) active uptake by vessel elements

(D) rhythmic contractions by cells in the root cortex

Short answer

(A) The option “mycorrhizae” is true.

(B) The option “pumping through plasmodesmata” is false.

(C) The option “active uptake by vessel elements” is false.

(D) The option “rhythmic contractions by cells in the root cortex” is false.

Step-by-step solution

Roots

Roots are underground anchorage organs of the plant. The roots firmly bind to the soil and prevent the plant from falling even in stormy conditions. The roots also prevent soil erosion that can help maintain the fertility of the soil in a particular region.

Explanation of option ‘(A)’

Mycorrhizae is a form of symbiotic association that is exhibited by the roots and the fungi. This type of association is very important as the fungi facilitate the easy absorption of water and minerals from the soil.

The plants produce sugar molecules that are supplied to the fungi. In return, the fungi abundantly supply minerals and water to the roots.

Thus, mycorrhizae enhance the uptake of minerals and water by the roots.

Therefore, the given option is true.

Explanation of option ‘(B)’

Plasmodesmata are membranous channels that facilitate the movement of nutrients from one region to the next. However, these membranous plasmodesmata channels cannot increase the water and mineral uptake in the roots. These channels also help in the movement of proteins and mRNA.

Thus, plasmodesmata do not enhance the uptake of minerals and water by the roots.

Therefore, the given option is false.

Explanation of option ‘(C)’

Vessel elements are building blocks that give rise to vessels and make up the water transport system in plants. They facilitate the movement of water from one region to another. However, these vessel elements do not enhance the water and mineral absorption by the roots.

Thus, vessel elements do not enhance the uptake of minerals and water by the roots.

Therefore, the given option is false.

Explanation of option ‘(D)’

The rhythmic root cortex contraction in plants is essential for transporting materials from the outer regions of the roots to the central zone. These minerals are then stored in the center as reserve food. Hence, they do not help in increasing water and mineral uptake in roots.

Thus, rhythmic root cortex contraction does not enhance the uptake of minerals and water by the roots.

Therefore, the given option is false.