Immune System

Question 1

What is the main difference between innate and adaptive immunity?

Answer 1

innate is very old and adaptive is more recent (evolution)

Question 2

What are the two parts of the innate immune system?

Answer 2

physical barriers and internal/cell based defenses

Question 3

What are the two parts of the adaptive immune system?

Answer 3

humoral and cellular immunity

Question 4

What do physical barriers do for the immune system?

Answer 4

physical walls to protect body (skin and mucous membranes)

Question 5

How does internal/cell based defenses help the immune system?

Answer 5

cells release chemicals when they recognize a foreign antigen

Question 6

What are receptors for foreign antigens called?

Answer 6

Pattern Recognition Receptors (PRR)

Question 7

What happens if there is no PRR to recognize a pathogen?

Answer 7

the innate cell cannot do anything (happens when there’s a new virus.. covid)

Question 8

What is an antigen?

Answer 8

anything that can be recognized by the immune system… some cause an immune response

Question 9

What are self antigens?

Answer 9

antigens present on normal human cells that are recognized but not attacked

Question 10

What is going on in the body if someone has an auto immune disease?

Answer 10

the body is attacking self antigens

Question 11

What happens when the body recognizes a foreign antigen?

Answer 11

immune response begins

Question 12

What are the cells of the innate immune system?

Answer 12

neutrophils, macrophages, natural killer cells

Question 13

Which cells can go in out out of blood and lymph nodes (basically anywhere)?

Answer 13

neutrophils

Question 14

What are the two types of macrophages?

Answer 14

resident and roaming

Question 15

What do resident macrophages do?

Answer 15

don’t really move around.. primarily found in digestive tract and lungs

Question 16

What do roaming macrophages do?

Answer 16

travel throughout body and go to injuries

Question 17

What do natural killer cells do?

Answer 17

travel through blood and lymph until they find a PRR to attach to cells and cause apoptosis

Question 18

What chemicals are released by macrophages and neutrophils?

Answer 18

prostaglandins and complement proteins

Question 19

What chemical is released by mast cells?

Answer 19

histamine

Question 20

What is released by virus infected cells?

Answer 20

interferons

Question 21

What do interferons do?

Answer 21

block viral replication and recruit phagocytes

Question 22

What do prostaglandins do?

Answer 22

activate neurons to cause pain

Question 23

What does histamine do?

Answer 23

causes vasodilation to increase blood flow which cause redness/heat; causes vessels affected by infection to become leaky and the fluid that leaves is what causes swelling

Question 24

What are the five cardinal signs of inflammation?

Answer 24

redness, heat, pain, swelling, loss of function

Question 25

What can cause inflammation?

Answer 25

trauma, chemicals, infection

Question 26

Why is inflammation a good thing?

Answer 26

helps to prevent spread, debridement, and is the first step in the repair process

Question 27

What are chemokines?

Answer 27

leukocytosis-inducing factors (bring WBC to infection)

Question 28

What happens when leukocytosis occurs?

Answer 28

neutrophils quickly come and monocytes follow

Question 29

How does a fever come about?

Answer 29

neutrophils/macrophages release pyrogens that go to the hypothalamus to tell the body to warm up

Question 30

What is the complement system?

Answer 30

a part of the innate AND adaptive immune system that is made up of plasma proteins that help fight infections

Question 31

How is the complement system activated?

Answer 31

1) antibodies from adaptive immune system binding 2) lectin presence on pathogen 3) spontaneous binding to pathogen

Question 32

What is the Membrane Attack Complex (MAC)?

Answer 32

hole produced by complements that helps with phagocytosis

Question 33

What are lectins?

Answer 33

sugars found on the membrane that help with adhesion

Question 34

What is one of the main goals of the adaptive immune system?

Answer 34

create antibodies to bind to foreign 'stuff' and activate the MAC in complement

Question 35

Adaptive immune system:

Answer 35

forms a specific, unique response to each intruder and results in a systemic reaction in which your whole body feels sicks but it has the ability to remember antigens so the next time you're exposed the reaction will be much quicker

Question 36

When is the humoral response activated?

Answer 36

when there is a clearly foreign pathogen and its easier to clear

Question 37

When is the cell mediated response activated?

Answer 37

when the pathogen is 'hiding' (virus or cancer cells)

Question 38

What are the adaptive immune system cells?

Answer 38

T cells, B cells, antigen-presenting cells (APC)

Question 39

Describe the structure of antibodies.

Answer 39

all antibodies have the same constant region but they also have a variable region and that is the part that binds

Question 40

How many foreign antigens can each antibody recognize?

Answer 40

one

Question 41

What does the antibody bind to?

Answer 41

antigen (antibody generating compound)

Question 42

What cells are activated by the humoral response?

Answer 42

naive B cells

Question 43

What two cells are formed as a result of B-cell activation?

Answer 43

memory B cells and plasma cells

Question 44

What are the two conditions in order for a B cell to mature?

Answer 44

have self tolerance and be immunocompetent (recognize only one antigen)

Question 45

What is negative selection?

Answer 45

if a B or T cell binds to and cannot release from an antigen, it gets killed

Question 46

What is positive selection?

Answer 46

if a B or T cell binds only weakly to just one antigen, it survives

Question 47

Does every B cell have the same antibody?

Answer 47

no

Question 48

What happens when the naive B cell finds its antigen?

Answer 48

activates the B cell (makes clones... memory or plasma cells)

Question 49

What does a plasma cell do?

Answer 49

release antibodies

Question 50

What does a memory B cell do?

Answer 50

use antibody as a receptor

Question 51

Why do all of the activated B cells have the exact same antigen?

Answer 51

somatic recombination

Question 52

How does somatic recombination ensure that the clones have the same antibody?

Answer 52

cuts out DNA

Question 53

What are the components of the variable region?

Answer 53

variabel sections (V), diversity sections (D), joining sections (J)

Question 54

What happens after the naive B cell chooses the 3 sections it wants?

Answer 54

makes an antibody with those three and all unused genes are removed from the genome

Question 55

What happens during the primary response?

Answer 55

antibodies in blood bind to antigens for the first time and the MAC is activated and neutralization and agglutination occur

Question 56

What is the secondary response?

Answer 56

second time the foreign antigen enters your body and the memory B cells that were formed during primary are activated to have a quick response (so fast you often time won't even feel sick)

Question 57

How do vaccinations work?

Answer 57

utilize the secondary response... your body is given an antigen from the pathogen which activates naive B cells to make memory B cells. after the second exposure your body already has antibodies to fight off the pathogen

Question 58

Why do we get boosters?

Answer 58

some viruses mutate and antigens change just enough that memory cells no longer bind