Answer: <em>The Bottleneck Effect</em>
Explanation:
A Bottleneck effect is the sharp reduction of numbers of a population through environmental effects or human activity. It causes a loss of the genetic pool and its variety; genetic variation lowers and increases with time as random mutations occur.
There is much more fresh water underground than on the surface. A rock layer must be porous and permeable to be a good aquifer. An impermeable layer makes up the bottom of an aquifer. The water table rises and falls with additions or subtractions to the groundwater system.
Water or other molecules move down their concentration gradient without any energy.........
difference - simple diffusion uses help of transporting protein in the membrane whereas osmosis uses no help.
the true statements about esophagus are :
- The esophagus is a muscular tube.
and
- The esophagus moves food from the mouth to the stomach.
i hope it helped.........