A substance that induces cancer. An essential component of animal cell membranes and the precursor for the formation of the steroid hormones. Not essential in the diet because it is synthesized by the body. Not found in higher plants or most bacteria. A thread-shaped structure, consisting mostly of DNA and supporting proteins, found in the nucleus of the cell, on which genes are arranged in a particular order.
Chromosomes exist in pairs in higher plants and animals.
Also known as rennin. Each DNA molecule consists of two strands in the shape of a double helix. Genes are made of DNA, and are responsible for the transfer of genetic information from one generation to the next. These breakdown products are then absorbed into the bloodstream. E enzyme A protein produced by living cells that regulates the speed of the chemical reactions that are involved in the metabolism of living organisms, without itself being altered in the process.