GALLBLADDER, PANCREAS, AND SPLEEN
The gallbladder,
already discussed, is a kind of "side pocket" in the channel through
which bile flows from the liver into the intestine, serving as a storage place.
The pancreas, which weighs about three ounces, lies high up in the abdomen,
deep behind the stomach. The pancreatic duct carries the digestive secretion,
pancreatic fluid, through a common opening with the bile duct, into the
duodenum.
The fluid contains three important enzymes: amylase acts on
carbohydrate foods; lipase functions in fat digestion; and trypsin is a
protein-digesting agent. Equally important are the islets of Langerhans which
are contained in the pancreas and produce insulin, a lack of which causes
diabetes.
The spleen, although often bracketed in people's minds with the
pancreas, is not an organ of digestion. Roughly fist-shaped and about six inches
long, it lies high up behind the stomach. In the unborn baby, the spleen plays
an important role in producing red and white blood cells. After birth, it no
longer manufactures red cells but still makes white cells.
In adult life, it
makes neither but does serve by doing the opposite-destroying old blood cells.
The spleen is not vital; it can be removed without harm. While it is a useful
organ, its functions can be performed elsewhere in the body. Normally, the
spleen cannot be felt from outside unless it enlarges considerably.
It usually does so when affected by disease, and in
extreme cases may increase fifty fold in size. Enlargement may carry some
hazard since the spleen, when engorged with blood, may produce severe internal
bleeding after a bump or knock that ordinarily would be trivial.
