How does the human body defend itself against pathogens Essay

How does the human body defend itself against pathogens - Essay Example Communicable illnesses are transmitted by germs particularly bacteria, viruses, and fungi. It is also important to explicate the fact that there are various points of entry of these germs into the human body. Some of these points of entry include the mouth, nose, and injured areas of the skin. Some illnesses are transmitted by insects such as malaria. There are three defence lines in the body. The first line of defence include the skin, second line of defence include the white blood cells, while the third line of defence involves the lymphatic system. Once germs or pathogens enter into the human body, the body reacts automatically to fight these germs. However, if the body is not in a position to confront these pathogens, the germs react by reproducing themselves and subsequently assault the numerous cells in the body in large numbers. The result is serious illnesses that can be life threatening. Other than pathogens, illnesses can also result due to abnormalities in the body itself. For instance, some diseases such as cancer are caused by abnormalities in the body, as mentioned earlier (Rosdahl and Kowalski, 2008). Nevertheless, the focus in this paper is pathogens. There are various ways that the body defends itself against disease causing pathogens or micro-organisms. The skin is the outer coating of the human body. In simple terms, the skin functions as a tool that blocks or barricades disease causing pathogens from entering the body. The outer layer of the skin is known as epidermis. This layer is important in defending the body against pathogens as it functions as a wall or blockade that blocks grime and pathogens out. The components that make up the skin are structured in a very compact way such that disease causing micro-organisms can penetrate only in case the skin is injured. The skin also prevents the entry of pathogens through notifying or sending signals to the immune system of an impending