Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Positive gravitropism is the growth of plant roots downward, towards the direction of gravitational pull. It ensures that roots anchor the plant and access water and nutrients from the soil.
5 Must Know Facts For Your Next Test
Positive gravitropism is mediated by the redistribution of auxin, a plant hormone.
Statocytes in the root cap detect gravity and aid in directing growth downward.
This response contrasts with negative gravitropism, where shoots grow upwards, away from gravity.
Root growth towards gravity helps stabilize plants and optimize nutrient uptake.
Mutations affecting gravitropism can lead to abnormal root development and impaired plant health.
Review Questions
Related terms
Auxin: A plant hormone that regulates growth and plays a critical role in positive gravitropism.
Statocytes: Specialized cells in the root cap that sense gravity and direct root growth.
Negative Gravitropism: The upward growth of plant shoots against the direction of gravitational pull.