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Unit V
Text 1.
Fleming Discovers Penicillin.
I.
First thoughts.
1. What associations does the word “penicillin” call
to mind?
2. Make the list of ideas.
II. Study the following words. Make sure you know them.
enzyme [ ] fluid [ ] tear [ ] jumble[ l]
lysozome [ ]
III. Read the text and do the tasks following it.
Who discovered penicillin?
Penicillin was the first antibiotic, a special drug that is very
good at killing bacteria. With antibiotics, many illnesses can
soon be cured that were once incurable. Penicillin was
discovered by accident by the British scientist Sir Alexander
Fleming in 1928. He noticed that a mold which had formed in a
dish in his laboratory was killing bacteria in the dish. From the
mold, penicillin was later prepared. In 1938, Howard Floery and
Ernst Chain found a way to make penicillin in large quantities.
Alexander Fleming returned to his research laboratory at St.
Mary’s Hospital in London after World War I. His battlefront
experience had shown him how serious a killer bacteria could
be, much worse even than enemy artillery. He wanted to find a
chemical that could stop bacterial infection.
He discovered lysozome, an enzyme occurring in many
body fluids, such as tears. It had a natural antibacterial effect,
but not against the strongest infectious agents. He kept
looking. Fleming had so much going on in his lab that it was
often in a jungle. This disorder proved very fortunate. In 1928,
he was straightening up a pile of Petri dishes where he has
been growing bacteria, but which had been piled in the sink.
He opened each one and examined it before tossing it into the
cleaning solution. One made him stop and say, “That’s funny.”
Some mold was growing in one of the dishes. …not too
unusual, but all around the mold, the staph bacteria had been
killed … very unusual. He took a sample of the mold. He
found that it was from the penicillium family, later specified as
Penicillium notalum. Fleming presented his findings in 1929,
but they raised little interest. He published a report on
penicillin and its potential uses in the British Journal of
Experimental Pathology.
IV. Comprehension check.
1. Match the following words and their meaning by
placing the proper letter on each black.
_1. toss a) cause (a vechile) to crash
_2. pile b) throw up
_3. fortunate c) go or penetrate below the surface
esp. of a liquid.
_4. bacteria d) lucky
_5. sink e) unicellular micro-organism lacking
an
organized nucleus
_6. infection f) microorganisms
_7. Mold e) disease
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