SECTION I - READING COMPREHENSION.

Directions: The following questions are based on a number of reading passages. Each

passage is followed by a series of questions. Read each passage carefully, and then answer

the questions based on it. You may reread the passage as often as you wish. When you have

finished answering the questions based on one passage, go right on to the next passage.

Choose the best answer based on the information given and implied.

Questions 1 – 4 refer to the following passage.

Passage 1 - Infectious Disease

An infectious disease is a clinically evident illness resulting from the presence of pathogenic

agents, such as viruses, bacteria, fungi, protozoa, multi-cellular parasites, and unusual proteins

known as prions. Infectious pathologies are also called communicable diseases or transmissible

diseases, due to their potential of transmission from one person or species to another by a

replicating agent (as opposed to a toxin).

Transmission of an infectious disease can occur in many different ways. Physical contact,

liquids, food, body fluids, contaminated objects, and airborne inhalation can all transmit infecting

agents.

Transmissible diseases that occur through contact with an ill person, or objects touched by

them, are especially infective, and are sometimes referred to as contagious diseases.

Communicable diseases that require a more specialized route of infection, such as through

blood or needle transmission, or sexual transmission, are usually not regarded as contagious.

The term infectivity describes the ability of an organism to enter, survive and multiply in the

host, while the infectiousness of a disease indicates the comparative ease with which the

disease is transmitted. An infection however, is not synonymous with an infectious disease, as

an infection may not cause important clinical symptoms. 1

1. What can we infer from the first paragraph in this passage?

a. Sickness from a toxin can be easily transmitted from one person to another.

b. Sickness from an infectious disease can be easily transmitted from one person to another.

c. Few sicknesses are transmitted from one person to another.

d. Infectious diseases are easily treated.

2. What are two other names for infections’ pathologies?

a. Communicable diseases or transmissible diseases

b. Communicable diseases or terminal diseases

c. Transmissible diseases or preventable diseases

d. Communicative diseases or unstable diseases

3. What does infectivity describe?

a. The inability of an organism to multiply in the host

b. The inability of an organism to reproduce

c. The ability of an organism to enter, survive and multiply in the host

d. The ability of an organism to reproduce in the host

4. How do we know an infection is not synonymous with an infectious disease?

a. Because an infectious disease destroys infections with enough time.

b. Because an infection may not cause important clinical symptoms or impair host function.

c. We do not. The two are synonymous.

d. Because an infection is too fatal to be an infectious disease.

Questions 5 – 8 refer to the following passage.

Passage 2 - Viruses

A virus (from the Latin virus meaning toxin or poison) is a small infectious agent that can

replicate only inside the living cells of other organisms. Most viruses are too small to be seen

directly with a microscope. Viruses infect all types of organisms, from animals and plants to

bacteria and single-celled organisms.

Unlike prions and viroids, viruses consist of two or three parts: all viruses have genes made

from either DNA or RNA, all have a protein coat that protects these genes, and some have an

envelope of fat that surrounds them when they are outside a cell. (Viroids do not have a protein

coat and prions contain no RNA or DNA.) Viruses vary from simple to very complex structures.

Most viruses are about one hundred times smaller than an average bacterium. The origins of

viruses in the evolutionary history of life are unclear: some may have evolved from plasmids—

pieces of DNA that can move between cells—while others may have evolved from bacteria.

Viruses spread in many ways; plant viruses are often transmitted from plant to plant by insects

that feed on sap, such as aphids, while animal viruses can be carried by blood-sucking insects.

These disease-bearing organisms are known as vectors. Influenza viruses are spread by

coughing and sneezing. HIV is one of several viruses transmitted through sexual contact and by

exposure to infected blood. Viruses can infect only a limited range of host cells called the “host

range”. This can be broad as when a virus is capable of infecting many species or narrow. 2

5. What can we infer from the first paragraph in this selection?

a. A virus is the same as bacterium

b. A person with excellent vision can see a virus with the naked eye

c. A virus cannot be seen with the naked eye

d. Not all viruses are dangerous

6. What types of organisms do viruses infect?

a. Only plants and humans

b. Only animals and humans

c. Only disease-prone humans

d. All types of organisms

7. How many parts do prions and viroids consist of?

a. Two

b. Three

c. Either less than two or more than three

d. Less than two