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A virus is a tiny germ that can infect the body. Different kinds of viruses can also infect animals and plants. There are thousands of kinds of viruses. There are about 100 kinds of viruses that cause colds. Viruses are much too small for scientists to see even with an ordinary microscope. Scientists must use a powerful electron microscope to see viruses. A virus is a pretty simple thing. It has two basic parts. It has an outer part called a protein coat. Inside the coat, it has genes. Genes are tiny structures that tell plants and animals how to grow and what shape to be. Each kind of virus infects, or attacks, a different type of cell. All parts of your body are made of units called cells. Cold viruses head for the lining of your nose or throat. Sometimes the cold virus spreads to the air passages that lead to your lungs. When a cold virus gets into your nose cells, it tries to take over. First, it takes off its protein coat. Next, it lets its genes go free. The genes command your nose cells to make more of the virus. The virus actually uses part of you to make copies of itself. More and more viruses grow in the cells that make up the lining of your nose. They burst out of one nose cell and head for other nose cells. This is how the infection spreads. An infected nose cell dies after the new viruses burst out. As your nose cells die, your head feels stuffy. Your nose starts to run. Dying cells make you feel sick. You can give your cold virus to someone else. You send out viruses when you cough or sneeze. Another person can breathe in the virus from the air near you. The virus gets on your hands when you blow your nose. Other people can get the virus by touching what you have touched and then touching their nose, eyes, or lips. You can help keep a cold virus from spreading by covering your mouth when you cough or sneeze. You should also wash your hands often. Different viruses spread in other ways. The rabies virus is in the saliva (spit) of an infected dog. The dog spreads the virus when it bites. Mosquito bites can also spread viruses. West Nile Virus goes from birds to mosquitoes when the mosquitoes bite the birds. The mosquitoes then spread the virus when they bite humans and other animals. The virus that causes AIDS is in blood and other body fluids. The viruses that cause cold sores and chicken pox get in through the skin. Other viruses live in food and get into people who eat the food. 1. The passage discusses all of the following EXCEPT ____. A. what a virus is B. what forms a virus C. how a virus attacks D. how viruses spread 2. The author starts the passage mainly by ____. A. defining virus B. warning about virus infection C. describing a virus D. mentioning an example of virus 3. Which of the following is NOT true about a virus according to the passage? A. The inner part of a virus is a gene. B. Viruses attack both animals and plants. C. Each type of virus affects a different type of cells. D. Viruses can be seen with powerful electron microscopes. 4. The word "passages" in the passage is closest in meaning to ____. A. column B. circle C. way D. bag 5. The word "it" in the passage refers to ____. A. protein coat B. nose cells C. cold virus D. the infection 6. The phrase "burst out of" in the passage mostly means ____. A. get in and destroyB. run away from C. get in and out D. break open 7. Which of the following is NOT true according to the passage? A. Cold viruses attack the nose before getting into the lung. B. When the cells are dying, people will feel sick. C. A virus can spread via animals infected with the virus. D. Viruses can infect people through the food people eat. 8. Which of the following could be most likely the reason for the writer to describe cold viruses? A. Cold viruses attack humans' nose before the lung. B. Cold viruses cause one of the most common diseases. C. It's very easy to prevent cold viruses from spreading. D. Cold viruses are actually beneficial to the human body. 9. What can you most likely infer from the passage? A. Eating various food types and keeping balance in nutrition is the key to a healthy body. B. Eating safe food and get vaccinated to prevent different diseases will help you keep fit. C. Eating healthy food and staying clean can help protect people from infection of viruses. D. Eating good food and staying away from animals will make humans free from diseases. 10. The overall tone of the passage is ____. A. argumentative B. narrative C. informative D. creative

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