Question

Assertion Aerenchyma is present in the leaves and petioles of hydrophytes.
Reason Aerenchyma imparts buoyancy to the hydrophytes.
A) Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
B) Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
C) Assertion is correct but Reason is incorrect
D) Both Assertion and Reason are incorrect

Answer 1

Hint: Aerenchyma is a tissue made up of a network of interconnected gas conducting intercellular spaces that provide oxygen to plant roots in hypoxic conditions. Aerenchyma, also known as aeriferous parenchyma, is a spongy tissue found in the leaves, stems, and roots of certain plants that allows gases to exchange between the shoot and the root.

Complete answer:
Plants that have adapted to life in water are known as aquatic plants (saltwater or freshwater). To distinguish them from algae and other microphytes, they are often called hydrophytes or macrophytes. A macrophyte is an emergent, submergent, or floating plant that grows in or near water. Macrophytes provide cover for fish, offer a substrate for aquatic invertebrates, produce oxygen, and provide food for some fish and wildlife in lakes and rivers.

Hydrophytes are plants that are indefinitely submerged in water. They can be submerged or partially submerged, with aerenchyma (large air space) in the leaves and petioles. Aerenchyma aids in the transport of oxygen produced during photosynthesis and allows it to freely diffuse to other sections, including roots in anaerobic soils.

These tissues also give the plants buoyancy. The presence of inflated petioles in Eichhornia (water hyacinth) allows the plants to float on the water's surface.

As a result, the correct response is 'Both Assertion and Reason are correct, and Reason is the correct justification for Assertion.' So correct answer is option ‘A’.

Note: Aerenchyma is a parenchymatous spongy tissue found in the stem, roots, and leaves that forms spaces, gaps, and air channels. It can be found in the roots, stems, and leaves of most aquatic plants.