Question

Pitcher plants have green leaves which can prepare food by photosynthesis then why does it eat insects?

Answer 1

Hint: Carnivorous plants grow in acidic swamp soils. This type of soil is poorly-rich in mineral salts and other essential elements for the proper growth and survival of a carnivorous plant. Most of the plants could not survive in these types of environments because those essential components are leached out of the ground via high water contents, but the carnivorous plants adapt themselves over time and they have different plans to compensate for deficient soil.

Complete answer:
-Insectivorous grown in bog areas where the soil is poorly rich or deficient in essential minerals like nitrogen and these nitrogen-deficient plants are recognized by yellowish leaf color, arrested growth, and early death. Nitrogen is an essential building block for proteins, enzymes, chlorophyll, and nucleic acids like DNA (Deoxyribonucleic acid). Nitrogen is a necessary element present in the soil and it is absorbed by plant roots, and it is also an important requirement for photosynthetic and metabolic reactions needed for the growth, development, and survival of the plants. Nitrogen is an essential component of chlorophyll, the compound by which plants use sunlight energy to produce sugar from water and carbon dioxide.
-Pitcher plants contain chlorophyll and are green in color so that they can prepare food via the process of photosynthesis but they don’t get the nitrogen from the soil in which they grow. So, insectivorous or carnivorous plants feed on the insects to collect the required amount of nitrogen they need for their growth and development.
-So, the answer is that to fulfill the nitrogen content which is essential for the photosynthesis process pitcher plants eat insects.

Note: Carnivorous plants have modified leaf structures to capture the prey and break down their bodies for the extraction of nitrogen and other essential elements which help in the process of building enzymes, chlorophyll, and other structures and also carry out the photosynthesis to make their own food.