Penicillin - GCSE Biology Definition
Reviewed by: Lára Marie McIvor
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Penicillin is a type of antibiotic used to treat bacterial infections. It was the first antibiotic to be discovered and is made from a mould called Penicillium. Penicillin works by killing bacteria or stopping them from growing, helping the body to fight infections. It is particularly effective against certain infections, such as strep throat and some types of pneumonia. Penicillin was discovered by Alexander Fleming in 1928 and has saved millions of lives. However, it is important to use penicillin and other antibiotics only when prescribed by a doctor to help prevent antibiotic resistance.
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