Intro to Immunology and the Immune System

Question 1

define immunity

Answer 1

state of protection from infectious disease

Question 2

define vaccination

Answer 2

administration of an attenuated (altered/weakened) strain of a pathogen to provide immunity to a disease

Question 3

describe herd immunity

Answer 3

the decrease of the number of individuals in a population that are susceptible to a disease that decreases the chances that a susceptible individual becomes infected; the fewer that can harbor a disease, the smaller the chances of it being passed on

Question 4

what are immunoglobulins also called?

Answer 4

antibodies

Question 5

where are immunoglobulins found?

Answer 5

in the body humors, or fluids

Question 6

what is humoral immunity?

Answer 6

the branch of the immune system found in the body humors

Question 7

what is passive immunity?

Answer 7

the transfer of immunity from one individual to another, or antibody transfer

Question 8

how long does passive immunity last? why?

Answer 8

generally short-lived because there is no transfer of the cells that produce the antibodies, just transfer of the actual antibodies

Question 9

what is active immunity

Answer 9

the production of one’s own immuntiy

Question 10

how is active immunity accomplished? (2)

Answer 10

1. vaccination

2. contracting the pathogen

Question 11

how long does active immunity last? why?

Answer 11

it is long term because the cells that encountered the pathogen are still present and can continue to protect

Question 12

what was the first immune cell discovered and in where?

Answer 12

lymphocytes; wer discovered the chicken

Question 13

what are T cells and B cells named that way?

Answer 13

for where they were discovered in the chicken
T cells discovered in the Thymus
B cells discovered in the Bursa of Fabricious, in Bone marrow everywhere else

Question 14

what is cell mediated immediated immunity?

Answer 14

branch of the immune system where cells eliminate the pathogen

Question 15

what are the 2 branches of the immune system?

Answer 15

humoral and cell mediated immunity

Question 16

what is an antigen?

Answer 16

any substance that elicits a specific response by B and T lymphocytes, or anything the body sees that shouldn’t be there

Question 17

what are the 2 types of antigens?

Answer 17

1. pathogenic

2. non-pathogenic

Question 18

what do pathogenic antigens do?

Answer 18

cause disease

Question 19

what do nonpathogenic antigens do?

Answer 19

don’t cause disease, can cause other things like allergies

Question 20

what can all cell-surface proteins do?

Answer 20

serve as antigens if they’re not in their normal place

Question 21

can one lymphocyte react to multiple antigens?

Answer 21

no; lymphocytes only express specific receptors for one specific antigen

Question 22

what is clonal selection?

Answer 22

when the binding of an antigen by a lymphocyte results in proliferation of the lymphocyte to produce many exact copies

Question 23

what comes after cloncal selection?

Answer 23

production of B cells that produce antibodies specific to the one antigen

Question 24

what MUST happen in order for an immune response to occur?

Answer 24

the proper lymphocte must come into contact with the proper antigen

Question 25

what are pathogens? give 4 examples

Answer 25

organisms that cause disease 1. viruses 2. bacteria 3. fungi 4. parasites

Question 26

in what 3 ways does recognition of a pathogen occur?

Answer 26

1. PAMPs and PRRs 2. lymphocyte diversity 3. tolerance

Question 27

what are PAMPs?

Answer 27

pathogen-associated molecular proteins; common foreign structures that characterize a whole group of pathogens

Question 28

give an example of a PAMP

Answer 28

gram negative lipopolysaccharide; not found in birds or mammals so recognized as other and bad

Question 29

what are PRRs?

Answer 29

pattern recognition receptors

Question 30

where are PRRs found?

Answer 30

found on immune cells

Question 31

what do PRRs do?

Answer 31

recognize PAMPs and lead to an immune event cascade

Question 32

describe lymphocyte diversity

Answer 32

population of B and T cells where each cell has many copies of receptors that are unique to one particular antigen

Question 33

how is lymphocyte diversity determined? is it genetic?

Answer 33

determined before pathogen contact and is NOT genetic

Question 34

describe tolerance in pathogen recognition

Answer 34

discrimination between self vs. nonself antigens; destruction of cells that are reactive to self-antigen

Question 35

what are the 3 components of the innate immune system?

Answer 35

1. physical and chemical barriers 2. PRRs 3. complement

Question 36

what is the innate immune system?

Answer 36

the part of the immune system that animals are equipped with from birth

Question 37

describe how the innate immune system functions (speed and specificity) and why

Answer 37

fast and nonspecific; does not recognize specific antigens, just commonalities amongst pathogens

Question 38

give 2 examples of physical barriers in the innate immune system

Answer 38

skin, mucus MEMBRANES

Question 39

give 2 examples of chemical barriers in the innate immune system

Answer 39

the mucus itself, secretions like HCl in stomach

Question 40

is the innate immune system effective?

Answer 40

yep, can neutralize a lot of pathogens and often works to prevent the adaptive immune system from needing to activate

Question 41

describe the adaptive immune system

Answer 41

learned immunity that is enhanced and adapts after encountering a specific antigen

Question 42

describe how the adaptive immune system works (speed and specificity) and why

Answer 42

is HIGHLY specific and forms memory, but response is delayed 5-7 days because need to make the cells for it

Question 43

in order to be effective, where should the immune system components be located? what need does this location then require?

Answer 43

spread throughout the body; need a way to communicate

Question 44

what are the 2 forms of communication in the immune system?

Answer 44

1. cell to cell contact | 2. chemical messengers

Question 45

when does cell to cell contact work as a method of communication in the immune system?

Answer 45

only if the cells are in close proximity to each other

Question 46

what do the chemical messengers of the immune system allow?

Answer 46

communication across long distances

Question 47

who are the 2 chemical messengers of the immune system?

Answer 47

1. cytokines | 2. chemokines

Question 48

what are cytokines?

Answer 48

the hormones of the immune system, the chemical messengers

Question 49

what are chemokines?

Answer 49

a type of cytokine that attracts other cells to the site of an infection

Question 50

what is the basis of memory in adaptive immunity?

Answer 50

primary, secondary, and following exposures

Question 51

describe the primary response of the immune system | what does it result in? how long does it take?

Answer 51

the first encounter with an antigenl results in clonal selection of effector cells and memory cells and takes 5-7 days

Question 52

what are effector cells?

Answer 52

fight infection, produced in large quantities in the primary response

Question 53

what are memory cells?

Answer 53

stick around for later exposure after the primary response, where they are produced in small numbers

Question 54

describe the secondary response | what does it eliminate? how does the host feel?

Answer 54

subsequent encounter with the same pathogen; eliminates the 5-7 day delay due to already made memory cells; usually clears antigen without host feeling symptoms

Question 55

how long do memory cells usually last?

Answer 55

very pathogen specific, broad range

Question 56

what is the basis for vaccination?

Answer 56

use of memory cells; vaccine is primary reponse and real world exposure is the secondary response