Presentation on theme: "Leukemia is characterized by abnormal white blood cells."— Presentation transcript:
1 KEY CONCEPT When the immune system is weakened, the body cannot fight off disease.
2 Leukemia is characterized by abnormal white blood cells. Leukemia is cancer of the bone marrow.characterized by immature B-cellscauses weakened immune system
3 Leukemia leads to opportunistic infections. occur because white blood cells cannot fight infectionsif immune system were healthy, it would fight these infections
4 HIV targets the immune system. The human immunodeficiency virus (HIV) is a RNA retrovirus.attacks and weakens the immune systemis transmitted by mixing infected blood with a bodily fluid
5 HIV infection leads to AIDS. T celldead T cellantibodyactivated B cellHIV reproduces in and destroys T cells.The body cannot replace T cells fast enough.T cells cannot help in immune responses.
6 AIDS is acquired immune deficiency syndrome. several opportunistic infections = infections succeed because T cells are gone—they take opportunity to survivevery low amount of T cells (less than 200 T Cells)