Nepenthes, Utricularia, and Drosera are all examples of insectivorous plants. Insectivorous plants are plants that have evolved to capture and digest insects or other small organisms in order to supplement their nutrient intake, especially in nutrient-poor environments.

Insectivorous plants have developed various mechanisms to attract, capture, and digest insects. These mechanisms can be broadly categorized into three main types: passive traps, active traps, and adhesive traps.

- Passive Traps: Passive traps are mechanisms that rely on the plant's structure to capture insects. Nepenthes, commonly known as pitcher plants, have passive traps in the form of modified leaves called pitchers. These pitchers are filled with a liquid that attracts insects. Once an insect lands on the slippery surface of the pitcher, it falls into the liquid and drowns. The plant then secretes enzymes to digest the insect and absorb nutrients from its body.

- Active Traps: Active traps are mechanisms that involve rapid movement to capture insects. Utricularia, commonly known as bladderworts, have active traps in the form of tiny bladder-like structures. These bladders have a trap door that is triggered when an insect touches sensitive hairs on the surface. The door opens, creating a vacuum that sucks the insect into the bladder. Enzymes are then released to digest the insect and absorb nutrients.

- Adhesive Traps: Adhesive traps are mechanisms that use sticky substances to capture insects. Drosera, commonly known as sundews, have adhesive traps in the form of glandular hairs on their leaves. These hairs secrete a sticky substance that traps insects. When an insect lands on the leaf, it becomes stuck and the plant wraps its leaves around the insect, releasing enzymes to digest it.

All three plants, Nepenthes, Utricularia, and Drosera, exhibit these insect-capturing mechanisms, making them insectivores. They rely on insects as a source of nutrients, particularly nitrogen, which is often limited in their habitats. However, it is important to note that these plants are still autotrophs as they can produce their own food through photosynthesis. The capture and digestion of insects serve as a supplement to their nutrient intake, rather than their sole source of energy.