The Immune System

Discover your body's amazing defense system! Learn about skin, mucus, antibodies, and vaccines protecting you from germs.

Introduction to the Immune System Here is a video introducing how the immune system works. The video goes into a lot of detail. You are not responsible for knowing or answering questions on the things mentioned in the video. It is just to watch and enjoy, the questions in the assignment are related to the text given above the questions. Body Defenses - Skin and Mucus(Excerpt from Steck-Vaughn "Wonders of Science- The Human Body") There are bacteria and viruses all around you. Yet you are healthy most of the time. This is true because your body has a way to protect you. The bodies first line of defense is the skin. The skin keeps bacteria and viruses from getting inside the body. If you cut your skin, then bacteria and viruses can get into the body through the cut. Bacteria and viruses can also get into you body when you breathe. Your body has another way to defend you. Your nose and throat are lined with tissues that make a liquid called mucus. The sticky mucus traps many bacteria and viruses. They leave the body in a cough or a sneeze. The tissue in the nose and throat also have tiny hairs. The hairs sweep mucus and particles up toward the mouth. Then they are swallowed and do not harm the body. 1. Bacteria and viruses can get into the body thought a cut in the skin. True False 2. The body cant defend itself from bacteria and viruses that get in through the nose. True False 3. How does your skin protect you from disease? Write a sentence to answer the question below. Body Defenses - Antibodies (excerpt from Steck-Vaughn "Wonders of Science - The Human Body" ) What happens if bacteria enter your skin through a cut? White blood cells destroy the bacteria. But many germs enter your body. They can get into your cells and start to reproduce. The white blood cells may not be enough to destroy them. Your body has another way of to defend itself. It makes chemicals called antibodies. A special antibody is made for each kind of germ that attacks you. Suppose the virus that causes measles gets into your body. If you have never has measles before, you will get sick. But your body makes antibodies that attack the measles virus. You get better. Some of those antibodies stay in your blood. The measles virus might get into your body again. But your body already has the antibodies to attack the virus. It quickly makes more. The virus is destroyed. You would not get the measles for a second time. 4. A special antibody is made for each kind of germ. True False 5. An antibody is a red blood cell. True False Body Defenses - White Blood Cells( excerpt from Steck-Vaughn - "Wonders of Science - The Human Body" Suppose you cut your hand. Bacteria get into your body thorough the cut. But your body can still defend itself. It can use its white blood cells. White blood cells are in your blood. They are always moving though your body. When you are cut, more white blood cells move to the area, they destroy bacteria. When the white blood cells destroy the bacteria , the skin around the cut gets red. It swells up. There may be pus in the cut. Pus is made of dead bacteria and white blood cells. It is a sign that the white blood cells are working. If you do cut yourself, try to keep bacteria from getting into your body. Wash the area around the cut to get rid of the bacteria on your skin. See a doctor if the cut is deep. 6. The steps below describe what happens when bacteria gets into your body. Put the steps in order. Bacteria get into the body. 2 Pus may form in the cut. 5 The skin is cut. 1 White blood cells move to the cut. 3 White blood cells destroy the bacteria. 4 Vaccines (Excerpt from Steck-Vaughn) When you were young, you went to the doctor a number of times. Each time you got a shot, or an injection. These shots were vaccines. Vaccines help your body protect itself from diseases like whooping cough, measles and mumps. How do vaccines work? Vaccines are made of bacteria or virus particles that are weak or dead. The bacteria or virus are not strong enough to make you sick. But the body still recognizes them as germs that can cause disease. So the body thinks that it is being attacked. It makes antibodies against the bacteria or virus. Then when you come in contact with the bacteria or the virus, you will not get sick. The antibodies made in your body will destroy the bacteria or virus. 7. You can get a disease by taking a vaccine. True False 8. Vaccines are made of dead white blood cells. True False 9. Why don't the bacteria and viruses in vaccines make you sick? Write a sentence to answer the question in the space below.