Some species of plants are insectivorous. Why?

1. Their growth in shady and dark places does not allow them to undertake sufficient photosynthesis and thus they depend on insects for nutrition
2. They are adapted to grow in nitrogen-deficient soils and thus depend on insects for sufficient nitrogenous nutrition
3. They cannot synthesize certain vitamins themselves and depend on the insects digested by them
4. They have remained in that particular stage of evolution as living fossils, a link between autotrophs and heterotrophs

Explanation

Option (b) is correct

• Insectivorous plants such as pitcher plants and sundews grow in nitrogen-deficient soils, especially in marshy or acidic environments. While they perform photosynthesis like other green plants, the lack of nitrogen limits their growth. To overcome this deficiency, these plants trap and digest insects to obtain nitrogen and other nutrients essential for protein synthesis and growth. They do not depend on insects because of poor photosynthesis, vitamin deficiency or evolutionary incompleteness. They use insects purely for mineral supplementation, not their main energy source.

Answer: (b) They are adapted to grow in nitrogen-deficient soils and thus depend on insects for sufficient nitrogenous nutrition