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.
A half marathon is a road running event of 21.0975 kilometres (13.1094 mi). It is half the distance of a marathon and usually run on roads. Participation in half marathons has grown steadily. One of the main reasons for this is that it is a challenging distance, but does not require the same level of training that a marathon does. In 2008, Running USA reported that the half marathon is the fastest growing type of race. A 2010 article by Universal Sports echoed the growing popularity of the distance.