Definition: Given a context passage, generate a question from the passage such that its answer is shortest continous span from the passage.
Input: The little girl pictured below ( Figure 1.1) has a scraped knee. A scrape is a break in the skin that may let pathogens enter the body. If bacteria enter through the scrape, they could cause an infection. These bacteria would then face the bodys second line of defense. The second line of defense is also nonspecific, fighting many types of pathogens. The bodys second line of defense against pathogens includes the inflammatory response. If bacteria enter the skin through a scrape, the area may become red, warm, and painful. These are signs of inflammation. Inflammation is one way the body reacts to infections or injuries. Inflammation is caused by chemicals that are released when skin or other tissues are damaged. The chemicals cause nearby blood vessels to dilate, or expand. This increases blood flow to the damaged area, which makes the area red and slightly warm. The chemicals also attract white blood cells called neutrophils to the wound and cause them to leak out of blood vessels into the damaged tissue. This little girl just got her first scraped knee. It doesnt seem to hurt, but the break in her skin could let pathogens enter her body. Thats why scrapes should be kept clean and protected until they heal. What do these white blood cells do at the site of inflammation? The main role of white blood cells is to fight pathogens in the body. There are actually several different kinds of white blood cells. Some white blood cells have very specific functions. They attack only certain pathogens. Other white blood cells attack any pathogen they find. These white blood cells travel to areas of the body that are inflamed. They are called phagocytes, which means eating cells. Neutrophils are a type of phagocyte. In addition to pathogens, phagocytes eat dead cells. They surround the pathogens and destroy them. Sometimes it is said that the phagocyte engulfs the pathogen, and then destroys it. This process is called phagocytosis. White blood cells also make chemicals that cause a fever. A fever is a higher-than-normal body temperature. Normal human body temperature is 98.6 F (37 C). Most bacteria and viruses that infect people reproduce fastest at this temperature. When the temperature is higher, the pathogens cannot reproduce as fast, so the body raises the temperature to kill them. A fever also causes the immune system to make more white blood cells. In these ways, a fever helps the body fight infection.
