Answers to Objectives for Section 31-4 1. Identify methods used to control pathogens. Antiseptics kill many pathogens and antibiotics kill specific bacteria 2. Explain how vaccines produce acquired immunity. They cause your immune system make B cells which make antibodies when you come in contact with that pathogen Carbon, Oxygen, Nitrogen, & Hydrogen make up 96 % of human body mass

Section 31-6 “Immune Diseases” How do the organ systems of the body work together to keep you alive?

KEY CONCEPT When the immune system is weakened, the body cannot fight off disease

A person with Leukemia has abnormal white blood cells Leukemia is cancer of the bone marrow Person has immature white blood cells causes weakened immune system

Leukemia leads to opportunistic infections occur because white blood cells cannot fight infections if immune system were healthy, would fight these infections

Cancer of the bone marrow Immature white blood cells Weaken immune system Opportunistic infections White blood cells can not fight infections It would be able to fight off these infections

HIV targets the immune system The human immunodeficiency virus (HIV) is a retrovirus attacks and weakens the immune system is transmitted by mixing infected blood with a bodily fluid

HIV reproduces in and destroys T cells dead T cell antibody activated B cell HIV reproduces in and destroys T cells The body cannot replace T cells fast enough T cells cannot help in immune responses

AIDS is acquired immune deficiency syndrome caused by HIV several opportunistic infections very low amount of T cells

Bodily fluids HIV reproduces in and destroys T cells The body cannot replace dying T cells fast enough T cells can not help in immune sytem response acquired immune deficiency syndrome caused by HIV several opportunistic infections very low amount of T cells

Objectives for Section 31-6 1. Explain what leukemia is. Skip 2 lines 2. Summarize how HIV affects the immune system. Carbon, Oxygen, Nitrogen, & Hydrogen make up 96 % of human body mass