1.The process of leaf color change. Leaves change color during the autumn because the amounts of pigments change as the leaves prepare to fall from trees. All leaves gradually lose chlorophyll during the growing season, and this loss accelerates before leaf fall.
2.The leaves in hot or dry environments may be adapted to reduce transpiration. For example, their stomata may be open at night and close midday. This is the reverse of what usually happens, and it means that the stomata are closet when the rate of transpiration would be greatest.
The answer is scientific theory. It amalgamates scientific law about objects and events that are widely accepted and tested. Scientific theory rationalizes phenomenon, that is not rigorously understood, through science. Examples of scientific theories today are the special relativity theory of Albert Einstein.
And if and because or up down and below or above or beneath
Its that food dropped on the ground is safe to eat and will not be covered in germs as long as its picked up within 5 seconds after its dropped.