2.79 plants and stimuli

http://www.youtube.com/watch?v=GxFF7BaVyQI

- stimuli are changes in the environment- light or temperature
- receptors detect the stimuli and then turns it into a response
- responses often take the form of growth- this is called a tropism, tropism that involves light is called phototropism
- tropism that involves gravity is called geotropism
- the connection that involves the receptor to the response is called plant hormones