Aim: How can misguided responses cause problems? Do Now: How does the immune system identify the difference between your cells and pathogenic organisms? Hw: Re-read pg Answer Review Questions 66, 67 on pg. 37 and Regents Practice C Question 44 on pg 42.

Immune System Malfunction The immune system can fail to recognize the difference between “self” and “non-self”. This can cause the immune system to attack and destroy an individuals own healthy cells/tissues/organs. Ex: destruction of pancreatic beta cells that produce insulin causing diabetes, rheumatoid arthritis, lupus.

DISORDERS OF THE IMMUNE SYSTEM Allergy: a condition in which a person's immune system is overly sensitive to environmental substances that are normally harmless. Antigens that cause allergic reactions are called allergens.

Examples of Allergens Ex. Animal dander (dead skin from cats & dogs)dust mites, pollen (powdery substance released by plants and trees)

Histamines Chemicals released by the immune system in response to allergens. Causes sneezing, increased mucus production, redness, swelling, rashes. Increase the permeability of the capillaries to white blood cells and some proteins, to allow them to kill pathogens in the infected tissues

Inflammation (Inflammatory response) characterized by four symptoms—redness, swelling, pain, and heat ; Histamine released causes blood vessels in the injured area to dilate,(redness) which makes them more permeable to tissue fluid. Fluid that leaks from the vessels helps the body destroy toxic agents and restore homeostasis.

Medications to treat Allergies Antihistamines: medications designed to reduce (minimize) the effects of histamines.

Aim: What is HIV? Do Now: June Hw: Finish extra credit, review topics 1,2,8, 9 ( ) for midterm. Tutoring Wed & Thursday after dismissal.

Autoimmune disorder  Disorder in which the immune system attacks your own healthy cells.  Ex: diabetes, rheumatoid arthritis, lupus,

HIV  Human Immunodeficiency Virus: virus that attacks white blood cells ( t-helper cells). This virus severely impacts the immune system.  HIV targets white blood cells and uses them to replicate, sending more viruses to other white blood cells.  HIV leads to AIDS (Acquired Immune Deficiency Syndrome).  HIV becomes AIDS when the body has only 1/6 of the amount of helper T-cells.

Biology Research  Learning about diseases by using different techniques which will help us treat infections.  Read Table 2-7 on pg. 36.