Unit 3: Immune System

What are the natural defenses?

skin

mucous membrane

destructuve acids and enzymes

What inhibits growth of microorgs on the skin?

enzymes and acids in sweat/oil

where on the skin can most bacteria not live?

epidermis or dry/dead skin

what do mucous membranes do?

protect from microbes in areas without skin

where are mucous membranes located?

lines respiratory and reproductive system, urinary tract

what kind of blood cells are in mucous membranes?

white

types of ways the body flushes stuff out

coughing, sneezing, vomiting, diarrhea

what are lysozymes?

destructive enzymes that destroy bacteria

function of lysozymes; examples

degrades cell walls;

stomach acids, tears, saliva, mild diarrhea

what are the non specific defenses?

natural killer cells and macrophages

inflammation

what does nonspecific denseness do?

reacts to tissue damage; macrophage engulf and destroy bacteria

what is in nonspec defenses?

WBC stem cells from bone marrow

what does immunological denfese do?

triggers apoptosis; recognize and destroy abnormal cells (tumors)

what is apoptosis?

programmed cell death

what does inflammation do?

Released chemicals that help restrict the spread of the infection and speed up the rate of tissue repair

what makes up inflammation?

Prostaglandins, Histamines

what does prostaglandin do?

increase blood flow

what is histamine?

chemical agent that triggers vasodilation; excess blood leads to swelling, redness, and heat

what is vasodilation?

the widening of blood cells

what is the purpose of a fever?

100^oF is too hot for most pathogens; chemicals induce drowsiness so that more energy can be devoted to defense and repair

what are the specific defenses?

cell mediated response (T Cells)

antibody mediated response (B Cells)

what is specific defense?

highly focused counterattack tailored to the invader

what are MHC proteins?

major histocompatibility complex protein; cell markers on cell membranes

what are antigens?

Recognized foreign cells by the immune system; triggers immune

responses

what do macrophages do?

consumes invaders with foreign MHC proteins by combining self with foreign body to activate specific defences; displays new MHC protein

where are macrophages found?

interstitial fluid

what are lymphocytes?

specialized white blood cells from stem cells in the bone marrow

what are the two branches of lymphoctyes?

T cells carry out cell-mediated immunity

B cells carry out antibody-mediated immunity (Humoral Immunity)

what are T cells? where are they from?

programmed cells that attack specific antigens; from the thymus

what are the types of T cells?

helper t cells

cytotoxic cells

suppressor cells

memory cells

what do helper t cells do?

coordinates between both branches

what do cytotoxic cells do?

rupture invader cell membranes

what do suppressor cells do?

inhibits branches from hurting non-antigen cells; ends when infection is contained

what do memory cells do?

rcognizes antigen and triggers response swiftly if seen again later

what are B cells?

cells that are activated by alerted macrophages/helper cells

what do b cells produce?

plasma cells and memory B cells

what does plasma do?

produce antibodies

what are antibodies?

proteins that bind with specific antigens; inactivates them

what happens when b cells bind with bacteria?

clumps antigens together to make easy to capture; inactivates bacteria’s toxins

what is clonal selection?

specific immune cells (B cells and T cells) are activated and multiplied only when they encounter a matching antigen

What is active immunity?

artificially induced immunity by vaccine; proactive

what do vaccines do?

stimulates the body to produce antibodies in its own defense

what are vaccines made of?

killed or weakened pathogens/activated toxins

what do vaccines produce in the body?

memory cells

what is passive immunity?

immediate protection for already infected people; reactive

what makes up passive immunity vaccines?

antibodies produced by other people/animals

do passive immunity vaccines make memory cells?

no

what makes a blood type?

antigens