PASSAGE TWO (Questions 3-6)
Vaccines are prepared from harmful viruses or bacteria and administered to patients to
provide immunity to specific diseases. The various types of vaccines are classified according to the
method by which they are derived.
The most basic class of vaccines actually contains disease-causing microorganisms that have
been killed with a solution containing formaldehyde. In this type of vaccine, the microorganisms
are dead and therefore cannot cause disease; however, the antigens found in and on the
microorganisms can still stimulate the formation of antibodies. Examples of this type of vaccine
are the ones that fight influenza, typhoid fever, and cholera.
A second type of vaccine contains the toxins produced by the microorganisms rather than
the microorganisms themselves. This type of vaccine is prepared when the microorganism itself
does little damage but the toxin within the microorganism is extremely harmful. For example,
the bacteria that cause diphtheria can thrive in the throat without much harm, but when toxins
are released from the bacteria, muscles can become paralyzed and death can ensue.
A final type of vaccine contains living microorganisms that have been rendered harmless.
With this type of vaccine, a large number of antigen molecules are produced and the immunity
that results is generally longer lasting than the immunity from other types of vaccines. The Sabin
oral antipolio vaccine and the BCG vaccine against tuberculosis are examples of this type of
3. Which of the following expresses the main idea of the passage?
Vaccines provide immunity to specific diseases.
Vaccines contain disease-causing microorganisms.
Vaccines are derived in different ways.
New approaches in administering vaccines are being developed.
4. How many types of vaccines are presented in the passage?
5. Which paragraph discusses vaccines made from dead organisms?
Which paragraph discusses
vaccines that do not contain the diseasecausing microorganism?
PASSAGE THREE (Questions 7-10)
A hoax, unlike an honest error, is a deliberately-concocted plan to present an untruth as the
truth. It can take the form of a fraud, a fake, a swindle, or a forgery, and can be accomplished in
almost any field: successful hoaxes have been foisted on the public in fields as varied as politics,
religion, science, art, and literature.
A famous scientific hoax occurred in 1912 when Charles Dawson claimed to have uncovered
a human skull and jawbone on the Piltdown Common in southern England. These human
remains were said to be more than 500,000 years old and were unlike any other remains from that
period; as such, they represented an important discovery in the study of human evolution. These
remains, popularly known as the Piltdown Man and scientifically named Eoanthropus dawsoni after
their discoverer, confounded scientists for several decades.
It took more than forty years for the hoax to be uncovered. In 1953, a chemical analysis was
used to date the bones, and it was found that the bones were modern bones that had been
skillfully aged. A further twist to the hoax was that the skull belonged to a human and the jaws to