Antitoxin, an tee TOK sihn, is a substance made by living cells that counteracts illness caused by a toxin. Toxins are poisons produced by living organisms, such as bacteria. Doctors use antitoxins to treat diseases, including tetanus (lockjaw) and diphtheria. Antitoxins are a kind of antibody that can cure or prevent diseases or make them milder (see Immune system).
Membrane is a term used to describe biological structures that cover surfaces and separate spaces in organisms. For example, cellular membranes… More>>
Cyst, sihst, is a sac in the body that contains fluid and has no outside opening. Cysts of the skin occur more often than others. These usually… More>>
Epithelium, ehp uh THEE lee uhm, is one of the major kinds of tissue formed in the bodies of human beings and some animals. It covers the body… More>>
Gangrene, GANG green, is the death of body tissues from lack of oxygen. It is caused by a loss of blood supply to areas of the body, often the… More>>
Connective tissue holds together and gives shape to body organs and tissues. It also holds organs in place and supports the body. Compared with… More>>
Alveolus
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