GED Science Practice 2025 – 400 Free Practice Questions to Pass the Exam

The term that refers to a plant hormone promoting root formation and bud growth is auxin. Auxins are a class of hormones in plants that play a crucial role in regulating various aspects of growth and development, including cell elongation, root initiation, and the formation of buds. They are instrumental in the overall growth patterns of plants, especially during the early stages of development when roots are forming and new shoots are emerging.

The other choices do not relate to a hormone involved in plant growth. Autotroph refers to organisms that can produce their own food, typically through photosynthesis or chemotrophy, rather than a hormone. Bacillus is a genus of bacteria that can play various roles in the environment, including some beneficial effects on plants, but is not a plant hormone itself. Bacteria, similarly, are a diverse group of microorganisms and do not directly pertain to plant hormone function. Thus, auxin is recognized specifically for its role in promoting root and bud growth in plants.