7.PCH.2

What does this standard mean a child will know and be able to do?

7.PCH.2.1 Analyze the immune system in terms of the organs, their functions, and their interrelationships.
The immune system provides protection for the body against pathogens (bacteria, viruses, fungi, parasites). The immune system is made up of many defenses to protect physical health. There are barriers that keep pathogens out of the body: skin, tears, saliva, mucous membrane, and stomach acid. There are other defenses that work inside the body: the lymphatic system and cells such as antigens, macrophages, T cells, B cells, and memory cells. The body reacts to antigens (substances that send the immune response into action) by making more antibodies (specific proteins that prevent antigens from harming the body).

The body is able to build immunity to many pathogens, making it far less likely that the person will experience the infection another time. Vaccines are weakened or dead pathogens introduced into the body to cause an immune response. The body creates memory cells to fight off that infection if the person is exposed to that virus or bacteria in the future. Certain vaccinations are required for school attendance to protect those for whom the vaccine does not work. The discovery of vaccines is considered one of the great public health achievements of the 20th century.

To protect the body’s immune system, one should practice good health. The body is better able to fight off infection if one participates in regular exercise, consumes vitamin-rich foods, manages stress positively, and gets sufficient sleep and rest. Students should be up-to-date with all vaccinations.
 * The student will describe the parts of the immune system.
 * The student will be able to explain how the immune system protects the body from infection and certain illnesses.
 * The student will practice healthy behaviors to protect the immune system.