DENDROLOGY

Detailed explanation-1: -During photosynthesis, plants take in carbon dioxide (CO2) and water (H2O) from the air and soil. Within the plant cell, the water is oxidized, meaning it loses electrons, while the carbon dioxide is reduced, meaning it gains electrons. This transforms the water into oxygen and the carbon dioxide into glucose.

Detailed explanation-2: -Carbon dioxide is a necessary element of photosynthesis in plants. It is used in optimum amount by plants to make their food. But a high concentration of carbon dioxide can damage the plant. High concentration of carbon dioxide is not only harmful to plants but also to environment.

Detailed explanation-3: -Final answer: Carbon dioxide is necessary for photosynthesis as it the major raw material used to form glucose.

Detailed explanation-4: -Carbon dioxide, water, and light are the ingredients plants need in order to make their food to grow. Carbon dioxide is a gas that we humans breathe out.