Answer: C. Always decreases but population size may increase or decrease.
According to the 10% law in ecological dynamics, the energy decreases by 10% when organism in lower trophic level being consumed by organism in the higher trophic level. The highest trophic level receives the lowest energy.
As matter and energy move from grasses (lower trophic level) to coyotes (higher trophic level) the amount of available energy will always decrease as per the 10% law but population size may increase or decrease.
The oesophagus is the region of the alimentary canal where the food passes without the absorption of nutrients. In oesophagus, we find peristalticmovement which is basically rhythmic contraction and relaxation of the oesophagus in order to facilitate the easy passage for the food to pass from mouth to stomach.
The oesophagus is a muscular tube which measures about 8 inches long.
