2.79 main points:
- Stimuli are changes in the environment (e.g. temperature changes and light changes)
- Plants have receptors to which can detect these stimuli to create a responses
- The responses often take before growth, this type of growth is called a tropism.
- Two types of responses are: Phototropism (related to light) and Geotropism (related to gravity)
- The connect between receptor and response is of plant hormones (e.g Auxin)
2.80 main points:
- Geo refers to gravity tropism refers to response of growth.
- An example is a seed, if we observe a seed growing we can see seed growing downwards we can describe this as positive geotropism.
- If it grows upwards it is called negative geotropism.
- If we rotate the seed around then geotropism will still happen.
2.81 main points:
- Photo refers to light tropism refers to response of growth (grows towards light)
- With uniform light growing all directions it will grow forward
- With some places with light, it will grow towards the light called lateral light.
- The hormones in the plant called Auxin leads plant to bend.