Read the following text and answer the questions:
INFLUENZA – VIRUS OR PLANT?
Read the text and answer the questions that follow: The influenza virus is a single molecule composed of millions of individual atoms. Although bacteria can be considered a type of plant, secreting poisonous substances into the body of the organism they attack, viruses, like influenza virus, are living organisms themselves. We may consider them regular chemical molecules since they have strictly defined atomic structure; but, on the other hand we must also consider them as being alive since they are able to multiply in unlimited qualities.
An attack brought on by the presence of the influenza virus in the body produces a temporary immunity, but, unfortunately, the protection is against only the type of the virus that caused the influenza. Because the disease can be produced by any one of three types, referred to as A,B, or C, and many strains within each type, immunity to one virus will not prevent infection by another type or strain.
Approximately every ten years, worldwide epidemics of influenza called pandemics occur. Thought to be caused by new strains of type–A virus, these pandemic viruses have spread rapidly, infecting millions of people. Epidemics, or regional outbreaks have appeared on the average every two or three years for type-A virus, and every four or five years for type-B virus.
1. With what topic is the passage primarily concerned?
a) the influenza virus
b) immunity to disease
d) chemical molecules
2. According to this passage, bacteria are
b) very small
c) larger than viruses
3. The word "themselves” in line 4 refers to
4. The word "strictly” in line 4 could best be replaced by
5. Why does the writer say that viruses are alive?
a) They have a complex atomic structure.
b) They move
c) They multiply.
d) They need warmth and light
6. The atomic structure of viruses
a) is variable
b) is strictly defined
c) cannot be analyzed chemically
d) is more complex than that of bacteria
7. The word "unlimited” in line 6 could best be replaced by which of the following?
a) very small
b) very large
c) very similar
d) very different
8. How does a body react to the influenza virus?
a) it prevents further infection to other types and strains of the virus.
b) it produces immunity to the type and strain of virus that invaded it.
c) It becomes immune to types A, B, and C viruses, but not to various strains within the types.
d) After a temporary immunity, it becomes even more susceptible to the type and strain that caused the influenza.
9. The author names all of the following as characteristics of pandemics EXCEPT
a) they spread very quickly
b) they are caused by the type-A virus
c) they are regional outbreaks
d) they occur once every ten years
10. The word "strain” in this text is closest in the meaning to: