Question

The gaseous wastes of respiration and photosynthesis in plants are removed through
A. Stomata of leaves
B. Lenticels of stem
C. Stomata and lenticels
D. None of the above

Answer 1

Hint: In plants, stomata is the pore present in the leaf surface through which plants can do photosynthesis and lenticel is the pore found in the stems that can transmit gases.

Complete answer:
- Excretion is a mechanism by which metabolic waste is removed from the body. In vertebrates, this is mainly done by the kidneys, lungs, and skin. This is in contrast to secretion, where the material may have particular roles after leaving the cell. Excretion is an important mechanism for all types of life. In unicellular species, waste products are emitted directly through the cell surface.
- Several chemical processes take place in the body during life events like cellular respiration. They are named as metabolism. These chemical reactions are produced by waste materials like carbon dioxide, salts, water, urea and uric acid.
- Accumulation of these wastes above the amount within the body is toxic to the body. These wastes are removed by excretory organs. This method of extracting metabolic waste from the body is known as excretion.
- Plants often produce waste materials, but very slowly and in very small quantities. They have no special organ for the elimination of their waste product. The waste products of the factory are carbon dioxide, water vapour and oxygen.
- Although carbon dioxide and water vapour are respiration waste products, oxygen is a photosynthesis waste product. These waste products are extracted by stomata in leaves and lenticels in stems and released into the air.
- During photosynthesis, carbon dioxide is taken from the atmosphere by the stomata and oxygen is emitted as a waste product. Lenticel is a porous substance in the surface of secondary organs and the bark of woody stems. It serves as a route for the direct transmission of gases between the internal tissues and the environment via the bark during respiration.

Thus, the correct answer is option C. i.e., Stomata and lenticels.

Note: Green plants produce as respiratory products carbon dioxide and water. In green plants, carbon dioxide released during respiration is used during photosynthesis. During photosynthesis, oxygen is produced and exits through root cell walls, stomata, and other pathways. Plants can get rid of extra water by guttation and transpiration.