Microscopic living things found everywhere - some are helpful, some can make you sick.

Bacteria are single-celled organisms that are among the oldest life forms on Earth. They live everywhere - in soil, water, hot springs, and even inside your body.
Many bacteria are helpful! Gut bacteria help digest food, soil bacteria recycle nutrients, and we use bacteria to make cheese, yogurt, and even medicines.
Go deeperSome bacteria cause diseases like strep throat, food poisoning, and pneumonia. Our immune system fights them, and doctors use antibiotics when needed.
Go deeperExtremophile bacteria live in incredible places - boiling hot springs, frozen Antarctic ice, deep ocean vents, and even inside rocks kilometres underground!
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