Zusammenfassung der Ressource
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
- The Positive Tropism: the plant grows
towards the stimulus
- The Negative Tropism: the plant grows
away from the stimulus
- Phototropism is where light is the stimulus and
geotropism is where gravity is the stimulus
- Light Stimulus: The shoot will grow toward the light and the
root will grow away from the light
- 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
- 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
- Cells in shoots grow more
- Cells in roots grow less