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.
There is a basic difference, because mass is the actual amount of material contained in a body and is measured in kg, gm, etc. Whereas weight is the force exerted by the gravity on that object mg.
