Medical Central: Organs

Today's topic is on a important set of parts within the body. So important and so interconnected, that if one goes "off" permanently, we die! Today we talk about... organs!

Organs
Before the last post, I mentioned that our Skin is an organ. But what's an organ? It's a part of the body that has at least two tissues combined... like muscle and nerve tissue. Usually, these tissues band together for a single purpose, and then they're called an organ.
We've got lots of organs. I mentioned Skin before, and some of the better-known ones are the heart, kidneys, and the stomach. There are some less-well-known ones, like the pancreas (while makes stuff for digestion) and the gallbladder (makes bile, which helps in digestion). The nutrient-absorbing intestines are organs too. Some organs, like the liver, multitask (though the liver primarily does digestion). Though some are really only doing one thing (the heart pumps blood which gives us energy, for example). Some organs even have similar jobs (the spleen and the kidneys are both cleaners, for example). Some do their jobs in interesting ways... the spleen, for example, cleans blood by removing no-longer-active cells. One famous organ is in charge of keeping other organs on the go... you know what I'm talking about: the brain!
Organs work together in systems. These are called "organ systems" usually do one big thing, with their own organs. The skeletal systems, the respiratory system, the circulatory system, and the digestive system are some examples of organ systems. However, these systems can't work alone. They all need each other to keep going!
Even if one organ's lights go out... good-bye person! However, technology has gotten so advanced, that we can either replace many of the organs, or assist them in their jobs so that they don't go out (and, therefore, we don't go out). Organs that are being used as replacements are kept and transported in special containers that keep the organ cold and sterile (AKA, germ-free and clean!). And these replacement organs can now be kept outside of the body for long periods of time if everything's done right! For example, now a replacement kidney can be kept outside of the body for days if everything's done right! Wow!