Holoparasites are plants that completely rely on other plants for their nutrients and energy. Unlike typical plants, they do not perform photosynthesis because they lack chlorophyll. Instead, they attach to the host plant's tissues and absorb water and nutrients directly from it. These plants often have specialized structures called haustoria, which penetrate the host's tissues. Examples of holoparasites include Rafflesia, known for its large flowers, and Balanophora, which can be found in tropical regions. Holoparasites play a unique role in their ecosystems, often affecting the health and growth of their host plants.