Auxins

Definition

Auxins are a class of plant hormones that play a crucial role in the regulation of plant growth and development. They are primarily responsible for cell elongation, root formation, and responses to light and gravity.

5 Must Know Facts For Your Next Test

1. Auxins promote cell elongation by loosening the cell wall through acidification.
2. They are produced in the shoot apical meristem and young leaves.
3. Auxins play a key role in phototropism, where plants grow towards light sources.
4. High concentrations of auxins can inhibit root growth while promoting stem growth.
5. Synthetic auxins, such as 2,4-D, are used as herbicides to control weed growth.

Review Questions

• What is the primary role of auxins in plant development?
• How do auxins influence phototropism in plants?
• Where are auxins primarily produced within a plant?

Related terms

Phototropism:

The orientation of a plant or other organism in response to light, typically causing it to grow towards the light source.

Gibberellins:

A group of plant hormones that stimulate stem elongation, seed germination, and fruit development.

Cytokinins: Plant hormones that promote cell division and delay senescence (aging) in plant tissues.