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.
Light year is nothing but the distance that the light travels in one year. The value is very huge. That's why we use that as some reference to measure the distance particularly in space. The distance travelled by light in a year is 9 trillion km( accuratelyâ¦.9.461e+12). The distance between earth and moon is appr.