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.
Finishing times for marathons (26.2 miles) range from a little over two hours for world-class, elite marathoners to 8+ hours for walkers. In terms of average marathon times, the median marathon finishing time in 2015 for men in U.S. marathons was 4:20:13 (9:55/mile pace), according to Running USA. The median finishing time for women was 4:45:30 (10:53/mile pace). Before running your marathon, it's definitely helpful to have an estimate of your marathon finishing time, so you know how to pace yourself properly.