What is the difference between apical dominance and geotropism?

Apical dominance refers to the phenomenon where the primary central stem of a plant grows more prominently than the side branches. This growth pattern is largely regulated by hormones, particularly auxins, which are produced at the tips of the shoots. The auxins promote upward growth, allowing the plant to reach light effectively and maximizing the photosynthetic potential. This phenomenon thus encourages vertical growth while inhibiting the growth of lateral buds, leading to a more elongated structure.

Geotropism, on the other hand, is the growth response of a plant to gravity. Roots generally exhibit positive geotropism, meaning they grow downward toward the gravitational pull. Stems, however, show negative geotropism, growing upward, away from gravity.

The distinction in the answer indicates that while both terms relate to the growth direction of plants, apical dominance is primarily concerned with the control of growth patterns affecting vertical stem growth, promoting it, while geotropism is about how the plant grows in response to gravitational forces, defining the directional growth of roots and stems. This highlights the nature of plant growth dynamics under different stimuli, leading to a complementary understanding of plant biology.