Control in plants

Plants need water and light for photosynthesis. Their responses, called TROPISMS, help make sure that any growth is towards light and water
1. The Positive Tropism: the plant grows towards the stimulus
2. The Negative Tropism: the plant grows away from the stimulus
3. Phototropism is where light is the stimulus and geotropism is where gravity is the stimulus
  1. Light Stimulus: The shoot will grow toward the light and the root will grow away from the light
  2. Gravity Stimulus: the shoot will grow against the force of gravity and the root will grow towards the force of gravity
Auxins are a family of hormones found in plants. They are mostly made in the tips of the shoots and roots, and can diffuse into other parts of the shoots or roots
1. They change the rate of elongation in the plant cells, controlling how tall they will become. Shoots and roots respond differently to high concentrations of auxins
  1. Cells in shoots grow more
  2. Cells in roots grow less

Resource summary

	Created by brooke.me over 11 years ago