The human body is not always able to fight off certain infections caused by bacteria on its own. Pneumonia, scarlet fever and strep throat are all caused by bacteria and can lead
to death if left untreated. Until recently, dying from some of these diseases was common.
Years ago, when someone became ill with an infection caused by bacteria such as
pneumonia, treatment options were limited. Bloodletting was one treatment that doctors
used. The sick would have blood released from their body because it was thought that too
much blood caused infections.
Fortunately, the discovery of penicillin changed the treatment of these types of infections.
Penicillin was accidentally discovered by Dr. Alexander Fleming in 1928. Dr. Fleming was
studying petri dishes that were filled with bacteria. Some of the petri dishes were
accidentally contaminated with a certain mold. The bacteria that had been contaminated
with mold didn't grow normally. Dr. Fleming realized the importance of his finding and
quickly worked to repeat his discovery.
Although it would be years until penicillin became widely available, its discovery changed
the world. During World War II, soldiers were easily treated with penicillin for diseases that
were considered deadly just a few years before. Today, penicillin and other antibiotics are
regularly used to treat illnesses.
How does the structure of the passage help support its central idea?
The chronological structure shows how deadly some infections were.
The compare and contrast structure shows how deadly some infections were.
The chronological structure shows the significance of the discovery of penicillin
The compare and contrast structure shows the significance of the discovery of penicillin