Immune System

Question 1

What is innate immunity?

Answer 1

generalized immunity with non-specific defense mechanisms

Question 2

What are the three levels of innate immunity?

Answer 2

1. physical and chemical barriers
2. innate inflammatory response
3. innate immune cells

Question 3

What else can innate immunity activate?

Answer 3

adaptive immunity

Question 4

What is an advantage and disadvantage of innate immunity?

Answer 4

it is fast but it doesn’t remember past infections

Question 5

What is the skin barrier in the innate immune system?

Answer 5

-sweat is antimicrobial and has lysozymes
-and you are covered in “good” bacteria and fungi

Question 6

What is the digestive, respiratory, and urogenital tracts barriers?

Answer 6

-secretory cells produce mucus to trap and destroy pathogens
-saliva has lysozymes that destroy pathogens
-tears and urine flush out pathogens
-low stomach pH kills pathogens

Question 7

What happens when we couldn’t keep the
pathogen outside of the skin?

Answer 7

then we can use innate immune cell receptors

Question 8

What are some innate immune cells?

Answer 8

mast cells, neutrophills

Question 9

How do the cells recognize the pathogens?

Answer 9

they recognize general pathogen parts (such as single strand DNA, bacterial membrane)

Question 10

What do innate immune cells do when they find a pathogen?

Answer 10

they trigger a transduction pathway

Question 11

What does the transduction pathway of innate immune cells release?

Answer 11

complement

Question 12

What is complement?

Answer 12

-poking holes in the pathogens to send signals of apoptosis

Question 13

Explain the cascade of inflammatory response?

Answer 13

1. injured cells secrete histamines (crying out for help)
2. blood vessels dilate (let more blood in) -causes area of infection to be hot and red
3. histamines make capillaries more permeable (easy for immune cells to get in) -causes swelling and pain
4. neutrophils eneter permeable capillaries

Question 14

What happens when neutrophils enter permeable capillaries?

Answer 14

1. they recruit monocytes (which mature into macrophages)
2. macrophages releases interleukin 1

Question 15

What are monocytes?

Answer 15

immature macrophages that mature when they are needed

Question 16

What does interleukin do, and what is the side effect?

Answer 16

they actually store iron in the spleen, because bacteria need iron to grow (this causes a fever)

Question 17

What is adaptive immunity?

Answer 17

memory immunity that recognizes specific pathogens

Question 18

What is an antigen?

Answer 18

something the body recognizes as non-self

Question 19

What are two types of adaptive immunity?

Answer 19

1. cell mediated
2. humoral

Question 20

What is a cytotoxic T-cell?

Answer 20

a white blood cell that has the ability to kill infected cells in the body

Question 21

What type of adaptive immunity is the cytotoxic t-cell a part of?

Answer 21

cell mediated

Question 22

How does a cytotoxic t-cell kill infected cells?

Answer 22

-it releases perforin which creates holes in the infected cell signaling apoptosis

Question 23

How do we activate cytotoxic t-cells?

Answer 23

an infected cell will present that it has been activated on its cellular membrane

Question 24

What is another way of activating cytotoxic t-cells?

Answer 24

1. if a macrophage has been eating the infecting cells then the antigen of the infected cell will be displayed on the macrophages surface
2. a helper t-cell is now activated and binds to the macrophage
3. the helper t-cell signals the n cytotoxic t-cells

Question 25

When a cytotoxic t-cell is activated, does it only kill the pathogen?

Answer 25

no, it actually divides to make cytotoxic t-cells and memory cytotoxic t-cells which help remember the infection for next time

Question 26

Are helper-t-cells only involved in the cell-mediated response?

Answer 26

nope, they are also involved in the humoral response

Question 27

What is the humoral response?

Answer 27

a response that involved b-cells and helper t-cells

Question 28

What happens during the humoral response?

Answer 28

1. macrophage eats infected cell 2. macrophage presents the antigen on its surface 3. helper t-cell binds to macrophage and sends signal to b (beta) cells 4. beta cells produce antibodies

Question 29

What are antibodies?

Answer 29

proteins that can bind to an antigen and hinder its ability to function

Question 30

Are antigens specific?

Answer 30

yes, antigens are very specific and can only bind to specific pathogens

Question 31

Do b-cells only produce antibodies?

Answer 31

nope, they clone themselves and produce memory beta cells which keep a memory to the antigen and pathogen they destroyed

Question 32

What are plasma b-cells?

Answer 32

b cells that produce antibodies

Question 33

What are MHC proteins?

Answer 33

proteins that bind peptide fragments of the pathogen and display on the cell surface

Question 34

What are MHC proteins 1?

Answer 34

-proteins that is found in every nucleated cell

Question 35

What do MHC 1 proteins activate?

Answer 35

cytotoxic t-cells

Question 36

What are MHC 2 proteins?

Answer 36

-proteins that is found in macrophages that ingested the infected cells

Question 37

What do MHC 2 proteins activate?

Answer 37

helper t-cells

Question 38

Can b cells be antigen presenting cells?

Answer 38

yes, the antigen can directly bind to b cells and b cells then act as APC

Question 39

What happens when a helper t-cell recognizes antigens on b cells?

Answer 39

it triggers a humoral response

Question 40

What happens when a helper t-cell recognizes antigens (MHC II) on macrophages?

Answer 40

trigger cytotoxic t-cells and a cell mediated response

Question 41

How does HIV affect helper t-cells?

Answer 41

-it attacks the helper t-cells directly -helper t-cells then die because the virus will replicate using the t-cells nucleus -this causes there to be no +director of communications" for the immune system -this leads the immune system to be more vulnerable

Question 42

What do the lymphoid organs do?

Answer 42

they support innate and adaptive responses by producing and maturing white blood cells

Question 43

What are primary lymphoid organs?

Answer 43

organs that make and mature immune cells

Question 44

What organ makes both b and t cells?

Answer 44

bone marrow

Question 45

Where do b cells mature?

Answer 45

bone marrow

Question 46

Where do t-cells mature?

Answer 46

thymus

Question 47

What is maturation?

Answer 47

white blood cells get trained to not recognize self cells (so that your own body doesn't attack you)

Question 48

What are secondary lymphoid organs?

Answer 48

where mature lymphocytes go to search for targets

Question 49

What are some secondary lymph organs?

Answer 49

lymph nodes, spleen, tonsils, appendix

Question 50

What does a naive cell mean?

Answer 50

unactivated cells

Question 51

What is a lymphocyte?

Answer 51

white blood cells

Question 52

What are the 3 APC?

Answer 52

dendritic cells, macrophages, and b cells