Find Out Which Organ Is Most Important

Within the organ, there's a network of bile ducts; bile, if you remember from the last chapter, is the greenish liquid produced in the liver that helps break down fats. The liver also uses bile to clear bilirubin from the blood. Biliwhat, you say? Bilirubin?it's a substance that comes from the breakup of hemoglobin in dead redblood cells. An increased level of bilirubin results in jaundice (a yellowing of the skin and all mucous membranes?that includes the eyeballs, where the yellowing is usually detected earliest and most easily), a sign of many liver diseases.

The various functions of the liver are carried out by the liver cells, called hepatocytes.

They are responsible for the organ's ability to regenerate; hepatocytes act as stem cells that can re-form liver tissue. These cells work primarily to serve these functions:

NUTRIENT BREAKDOWN We all may know that skim milk is good for your bones, fish is good for your muscles, and olive oil is good for your heart. But only a weird cartoonist thinks that your bones actually bathe in milk or there's a blood vessel that transports fresh olive oil through a side door in the aortic chamber.

Everything we eat and drink has to be broken down into different chemicals before it can get to work on helping (or, in the case of some foods and drinks, harming) your body. And that's one of the primary jobs of the liver.

STORAGE AND CREATION The liver, which makes protein and stores glucose, vitamin B12, and iron, helps get nutrients to your body by processing all foods? carbohydrates, protein, and fat?into glucose that can be used throughout your body. Glucose is a fancy name for a specific and common sugar (yup, everything is turned to sugar). Iron stores in the liver are great enough for most people that iron supplements are not usually needed, except in people with iron deficiency anemia, which is the most common nutritional deficiency worldwide. The liver also serves as the initial source of glucose when you rush the hot dog stand at halftime (even be-fore you get there), since the sugar in your blood provides only ten minutes of energy.