Host plants are specific types of plants that provide food and habitat for certain insects, animals, or other organisms. These plants are essential for the survival and reproduction of their associated species, as they offer the necessary nutrients and shelter. For example, the monarch butterfly relies on milkweed as its host plant, where it lays eggs and the caterpillars feed. Different organisms have evolved to depend on particular host plants, which can influence their distribution and behavior. The relationship between host plants and their associated species is crucial for maintaining biodiversity and ecosystem health. Without these plants, many species would struggle to survive.