Plants use direct environmental stimuli for orientation in growth and movement. This is called tropism. The responses of the plant may be toward (positive) or away (negative) from the external stimulus or stimuli.Click the links below to learn more about the different types of stimuli and the plants reaction to it:Phototropism-Reaction to light and different wavelengths.his is called tropism. The responses of the plant may be toward (positive) or away (negative) from the external stimulus or stimuli. Click the links below to learn more about the different types of stimuli and the plants reaction to it:
I'm thinking about training for a marathon. A marathon is 26.2 miles or 42 kilometers. Although some marathons differ in their terrain (some are very flat, some are extremely hilly) and degree of difficulty, the distance is always 26.2 miles.
If you can run a marathon, you are in good shape. When your body can take the rigors of running a 26-mile, 385-yards, you have passed a major fitness test. However, you are not running the longest race. There are ultramarathon races for those who just canât get enough and 26 miles is just the beginning. Here are the five longest running races in the world.