In plants, a tropism refers to the growth of a plant in response to an external stimulus. Plants can grow either towards or away from stimuli. The curving of plants is frequently due to differential growth, where different sides of a stem or root grow at different rates.n plants, a tropism refers to the growth of a plant in response to an external stimulus. Plants can grow either towards or away from stimuli. The curving of plants is frequently due to differential growth, where different sides of a stem or root grow at different rates.
There is an exact numerical answer to this question. By definition, 1 light year is exactly 9,460,730,472,580,800 meters. By definition, 1 mile is exactly 1,609.344 meters. So, 1 light year is exactly 5,878,625,373,183 and 849/1397 miles, by definition. Written May 20 â¢ View Upvotes.
a light year is a unit of distance it is the distance that light can travel in one year light moves at a velocity of about 300000 kilometers km each second so in one year it can travel about 10 trillion km