Question

23. Aerenchyma provides a) Mechanical strength to plants b) Extra space for photosynthesis and storage of food c) Flexibility to plants d) Buoyancy to hydrophyte plants​

Answer 1

Answer:- Buoyancy to hydrophytic plants

Explanation:

Aerenchyma is the spaces or air channels in the leaves, stems and roots of some plants, which allows exchange of gases between the shoot and the root. The channels of air-filled cavities provide a low-resistance internal pathway for the exchange of gases such as oxygen and ethylene between the plant above the water and the submerged tissues.

Aerenchyma is also widespread in aquatic and wetland plants which must grow in hypoxic soils. The large air-filled cavities provide a low-resistance internal pathway for the exchange of gases between the plant organs above the water and the submerged tissues. This allows plants to grow without incurring the metabolic costs of anaerobic respiration.

Some of the oxygen transported through the aerenchyma leaks through root pores into the surrounding soil. The resulting small rhizosphere of oxygenated soil around individual roots support microorganisms that prevent the influx of potentially toxic soil components such as sulfide, iron and manganese.

So, aerenchyma provides buoyancy to hydrophytic plants and not promoting nature of photosynthesis, flexibility to plants or mechanical strength to plants.

Thus, the correct answer is option D .