Imagine that a potential pathogen has been able to get through the skin, the first line of body defense. what three general defense mechanisms can the body use as a second line of defense to prevent the pathogen from causing a major infection?

There are few cells in the body that do not undergo mitosis: most somatic cells divide regularly, some more than others. take for example the cells that line the digestive tract. these cells must be frequently replaced because they are constantly eroded by the movement of food through the tract. what mechanism(s) is/are in place to ensure that these cells are exact copies of the mother cell