Images Dated 16th December 2003

Coloured SEM of a liver cell known as hepatocyte

Liver cell. Coloured scanning electronmicrograph of a single human liver cell also knownas hepatocyte. Hepatocytes have a polyhedralshape, having five to twelve sides, with adiameter of about 12 to 25 micrometers.Hepatocytes perform a multitude of functions: theysynthesise various plasma proteins includingalbumin and clotting factors, regulate the bloodlevel of amino acids and secrete bile whichcarries away waste products from the liver andhelps the breakdown of fats in the smallintestine. Bile is drained away in the bilecanaliculi (green) and is stored in the gall-bladder. Magnification: x1725 at 6x7cm size

DNA

DNA, conceptual computer artwork. Deoxyribonucleic acid is the molecule that controls the growth, development and functioning of all living things. It comprises a pair of sugar-phosphate strands spiralling around each other in a double helix. The strands are linked by the interactions between bases on each strand. There are four types of base: adenine (A), thymine (T), cytosine (C) and guanine (G). A only links to T, and C only links to G, making each strand complementary to its partner. DNA encodes information as a sequence of base pairs. The strands contain sections called genes, which are recipes for proteins, the main structural and functional components of the body

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