EXAM 4 P2

Question 1

B cell receptor proteins

Answer 1

how B cells express antibodies on their surface

Question 2

what happens if the B cell receptor binds a foreign antigen

Answer 2

it is taken up and expressed on the cell surface in the context of a MHC 2 complex

Question 3

first check

Answer 3

uptake and degradation of the pathogen

first check is that it’s a non-self antigen

Question 4

second check

Answer 4

done by TH2 cells that release cytokines
the B cell now multiplies, with some differentiating into plasma cells
job is to breakout lots of antibodies and release them into the body.

Question 5

what are cytokines

Answer 5

molecules that activate the B cell and say it’s correct in finding the antigen (aids with plasma formation)
released by TH2 cells

Question 6

TH2 cells

Answer 6

recognize the B cell that is expressing a foreign antigen in the class 2 MHC.
release cytokines in response
innate response is immediate with foreign material

Question 7

about how long does antibody production take

Answer 7

2 weeks, vaccines

Question 8

memory cells

Answer 8

remain in the body for several years (long life)
differentiated B cell
able to remember they saw the antigen so if they make contact with it again, it will respond immediately.
they do not need a TH2 to bind the antigen
response is quick (1-2 days)

Question 9

antibody structure

Answer 9

2 heavy chains and 2 light chains
proteins, variable and constant regions, disulfide bonds
IgG, IgM, and IgA

Question 10

IgG

Answer 10

most abundant in the blood and able to cross the placenta

allows a babies immune system to be completely developed and contain antibodies from the mothers blood. high affinity

Question 11

IgM

Answer 11

most common B cell receptor
can form a pentameric structure, the first in the most rapid response (lymph and blood). first plasma cells produced make this form.
low affinity antigen binding, but has many binding sites
bonds are not tight

Question 12

IgA

Answer 12

forms a dimer structure

found in mucus membranes (lungs, mouth, digestive and urinary tract)

Question 13

neutralizing antibodies

Answer 13

block the function of the antigen when directly bound to the antibody.
bind to the toucan protein and inhibit toucan from binding to the cell.
bind virus spike protein to inhibit virus from binding to the host cell

Question 14

Tc cells

Answer 14

recognize virus infected cells

assists in the killing of infected cells when antibodies mark the infected for attack with the Tc

Question 15

opsonization

Answer 15

increased phagocytosis

Question 16

complement

Answer 16

series of proteins the body produces that circulate your blood all the time, interacting with antibody-antigen complexes
cause lysis/destruction of bacterial cells and opsonization

Question 17

how vaccines work

Answer 17

first antigen injection has primary response from IgM
boosters activate memory cells
secondary response is IgG, more rapid

Question 18

types of vaccine components

Answer 18

whole bacterial cells that have been killed by heating or chemical treatment
whole virus particles that have been killed

Question 19

attenuated cells

Answer 19

have a mutation that prevents them from actually causing the disease

Question 20

toxoids (inactivated toxin proteins)

Answer 20

proteins that actually cause symptoms of the infection without the toxic proteins activated
anthrax and tetanus vaccine

Question 21

recombinant/synthetic antigens

Answer 21

pure proteins (HPV vax) and mRNA (COVID vax)

Question 22

phagocytes role with antigen presentation

Answer 22

put fragments into their MHC and present it to cells of the adaptive response (T cells)
TH1 is activated and releases cytokines, causing inflammation
TH2 activates B cells to multiply and produce antibodies

Question 23

host

Answer 23

organism that houses a microbe

Question 24

colonization or infection

Answer 24

relates to growth of a microbe within the host
colonization relates to non-pathogens
infection relates to pathogens

Question 25

disease

Answer 25

an injury or impaired function of the host

a microbe colonizes you but doesn’t cause problems

Question 26

pathogen

Answer 26

a microbe that causes disease

Question 27

obligate pathogens

Answer 27

only found on the host and must infect the host in order to grow and reproduce

Question 28

opportunistic pathogens

Answer 28

commonly found in non-disease states

do not normally cause disease, but can impair host

Question 29

pathogenicity

Answer 29

ability of a microbe to cause disease
qualitative
yes or no question

Question 30

virulence

Answer 30

measure of the degree of pathogenicity of a microbe
the relative severity of symptoms
quantitative
most gut E. coli have low virulence

Question 31

roles of normal (microbe) flora of the human body

Answer 31

competes with pathogens for space and nutrients
produces products that inhibit pathogens
synthesize vitamins for the host (gut)
stimulate development of immune tissues

Question 32

what surfaces do microflora colonize

Answer 32

skin surfaces and mucus membrane surfaces

approx. 10^13 human cells and 10^14 bacterial cells