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Waveform Audio File Format  |  1995-06-29  |  437.7 KB  |  1 channel  |  22,050 sample rate  |  40 seconds  |  [TEXT/LMAN]
Transcription: Some bacteria, viruses, protists, and fungi, often called germs, can invade living tissues and may kill the organism unless it defends itself. Animals' skins act as germ-proof barriers, but if germs get into the body through cuts, breathing, or food, two defense mechanisms fight infection. One is nonspecific. Germs are hunted and eaten by white blood cells that patrol the body. The other, the immune system, is specific. Chemicals called antibodies are produced by white blood cells to destroy specific germs. Plants have only a protective epidermis or skin to keep germs out.