What describes the growth of plant parts in response to gravity?

The term that describes the growth of plant parts in response to gravity is geotropism. This phenomenon is crucial for plants as it ensures that roots grow downward into the soil, where they can access nutrients and water, while stems and leaves grow upward toward the light source. This gravitational response helps plants establish a stable orientation in their environment, enabling effective nutrient uptake and photosynthesis.

Phototropism, on the other hand, refers to a plant's growth response to light, where plants bend toward the light source to maximize their exposure to sunlight. Hydrotropism concerns a plant's growth toward moisture. Lastly, chlorotropism is not a widely recognized term in plant biology and does not pertain to a specific growth response like the others do. Understanding these different tropisms helps clarify the various ways in which plants interact with their environment.