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.
It is so fast that light can travel about seven times around Earth in one second!! Thatâs about light. What is a light year then? Light Year is the distance that light can travel in one year. Considering that light can travel about 300,000 kilometers (km) each second, in one year, it can travel 9,500,000,000,000 kilometers. Phew! It would be easier to say that one light year is about 10 trillion km.