Into this duct the ranks of cells around it pour out the peptic juice.] Digestion in the Stomach.

Although usually a single, pear-shaped pouch, the stomach, during digestion, is practically divided into two parts by the shortening, or closing down, of a ring of circular muscle fibres about four inches from the lower end, throwing it into a large, rounded pouch on the left, and a small, cone-shaped one on the right.
The gullet, of course, opens into the large left-hand pouch; and here the food is stored as it is swallowed until it has become sufficiently melted and acidified (mixed with acid juice) to be ready to pass on into the smaller pouch.

Here more acid juice is poured out into it, and it is churned by the muscles in the walls of the stomach until it is changed to a jelly-like substance.
Digestion in the Small Intestine.

The food-pulp now passes on into the _small intestine_, where it is acted upon by two other digestive juices--the _bile_, which comes from the _liver_, and the _pancreatic juice_, which is secreted by the pancreas.
The liver and the pancreas are a pair of large glands which have budded out, one on each side of the food tube, about six inches below where the food enters the small intestine from the stomach.

The liver[5] weighs nearly three pounds, and the pancreas about a quarter of a pound.
Of these two glands, the pancreas, though the smaller, is far more important in digestion.