Questions

On December 21, the earth is in an equivalent position on the opposite points in its orbit, So the South pole is tipped towards the sun and North pole away from it resulting in 24 hours of darkness at the North pole, as the sun is overhead on the Tropic of Capricorn. This phenomenon is winter solstice; while on June 21, North pole is tipped towards the Sun but the South pole is tipped away from the sun resulting in 24 hours of darkness on the South Pole, as the sun is overhead on the Tropic of Cancer.This phenomenon is summer solstice; while Aphelion is the position of the earth in its orbit when it is at its distant point from the sun.

BEML - Bharat Earth Movers Limited is the PSU which had received 'Top Challengers' and 'Best Mining Equipment Seller Award' recently for the year 2017 - 2018. 

The plant cell organelles, "The power house of the cell" mitochondria and the chloroplasts contains their own DNA and ribosomes.

Humans cannot digest cellulose because they are lacking with the enzymes responsible to breakdown the beta acetal linkages.