Final Exam

Question 1

pathogens enter the cell via what?

Answer 1

Adherence

Question 2

Bacterial Adherence can be facilitated by what?

Answer 2

Extracellular macromolecules not covalently bonded to the bacterial cell surface (Fimbriae & Pili)

Question 3

Invasion of a pathogen is through what?

Answer 3

Epithelium Layer of the skin

Question 4

During invasion, how does a pathogen enhance its virulence?

Answer 4

breaking down or altering host tissue to provide access to nutrients

Question 5

How does an infecting pathogen protect itself from the hosts immune system?

Answer 5

by incorporating some part of the host cell into itself, tricking the host immune system

Question 6

Name all of the Exotoxins covered in class

Answer 6

1) Cytolytic Toxins
2) A-B Type Toxins
3) Enterotoxins

Question 7

Cytolytic toxin mechanism

Answer 7

degrade cytoplasmic membrane, causing cell lysis and death

Question 8

A-B Type Toxin Mechanism

Answer 8

1) B subunit binds to a specific molecule on the host cell
2) toxin is taken up via endocytosis
3) toxin subunits seperate allowing (A) subunit (toxin) to enter the cytoplasm

Question 9

3 Types of A-B Toxin

Answer 9

1) Diphtheria
2) Tetanus
3) Botulinum

Question 10

Botulism mechanism

Answer 10

blocks the release of Acetylcholine, inhibiting contraction

Question 11

Tetanus Mechanism

Answer 11

binds to inhibitory interneurons, preventing release of glycine and relaxation of the muscles

Question 12

Diphtheria mechanism

Answer 12

causes protein synthesis to stop

Question 13

What do enterotoxins do?

Answer 13

Mess with the ion balance in the gut epithelium

Question 14

Endotoxins do what?

Answer 14

infect the lipopolysaccharide portion of the cell

Question 15

How can you detect Endotoxins?

Answer 15

LAL assay

Question 16

What do Type III Secretion pathogens do?

Answer 16

induce apoptosis

Question 17

How do Type III Secretion pathogens enter the cell?

Answer 17

mess with actin polymerization

Question 18

What is innate immunity?

Answer 18

No previous exposure

Question 19

What does the innate immune system have the ability to do?

Answer 19

non-inducible ability to recognize and destroy an individual pathogen or its products

Question 20

Adaptive Immunity

Answer 20

dependent on previous exposure

Question 21

what does the adaptive immune system have the ability to do?

Answer 21

acquired ability to recognize and destroy a particular pathogen or its products

Question 22

Adaptive Immunity Mechanism

Answer 22

1) recognize the pathogen antigen

2) T and B cells activated

Question 23

Antibody Mechanism

Answer 23

B cells display antibodies on their surfaces that directly interact w/ antigen to cause B cells to ingest pathogen via phagocytosis

Question 24

Ig proteins do what?

Answer 24

interact w/ antigenic determinants

Question 25

Ig proteins are found where?

Answer 25

milk. serum, and gastric secretions

Question 26

Major Histocompatibility Complex are what?

Answer 26

proteins that are expressed on the cell surface that reflect the composition of the protein inside the cell

Question 27

Relationship between MHC and TCR

Answer 27

TCRs bind only to MHC molecules having foreign antigens embedded in the MHC structure

Question 28

T cell Receptor

Answer 28

molecule found on the surface of T cells that is responsible for recognizing antigens bound to Major Histocompatibility complex (MHC) molecules

Question 29

What is Inflammation?

Answer 29

a non-specific reaction to noxious stimuli

Question 30

What mediates inflammation

Answer 30

Cytokines and Chemokines

Question 31

What does inflammation do?

Answer 31

Isolates and limits tissue damage and destroys damaged cells as well as the pathogen

Question 32

Mechanism of inflammation?

Answer 32

1) Interleukins attract Neutrophiles | 2) activated neutrophiles release chemokines to recruit macrophages by guiding them along the chemkine gradient

Question 33

What are Cytokines?

Answer 33

proteins that allow for intracellular communication in the immune system

Question 34

What are Chemokines

Answer 34

Small group of proteins that function as chemoattractants for phagocytes and lymphocytes

Question 35

What is Somatic Recombination?

Answer 35

Mechanism that creates diversity of T and B cells

Question 36

How does Somatic Recombination work?

Answer 36

During development of B cells in the bone marrow, heavy chains and light chains are rearranged to create various combinations

Question 37

What is compliment fixation?

Answer 37

The binding of active serum complement to an antigen-antibody pair.

Question 38

Cloning Selection, T cells must?

Answer 38

be able to distinguish between themselves and nonself antigens

Question 39

Tolerance

Answer 39

T cell is unresponsive to itself, meaning it can ID cells that dont belong in the host

Question 40

Cloning selection Theory

Answer 40

each antigen-reactive B and T cell has a cell surface receptor for a single antigen epitope

Question 41

Positive Selection

Answer 41

T cells that recognize MHC peptides are retained

Question 42

Negative Selection

Answer 42

T cells that pass the positive selection and strongly bind to self antigens are selected against

Question 43

T and B cell activation require what?

Answer 43

2 molecular signals 1) 1st signal interacts w/ antigen through Ig or TCRs 2) 2nd signal is necessary for them to respond to antigen

Question 44

Selective Media

Answer 44

allows some organisms to grow while inhibiting others

Question 45

Differential Media

Answer 45

allows identification of organisms based on their growth and appearance on the medium

Question 46

Enteretube

Answer 46

a multiple-test system which combines 9 biochemical tests, useful in the identification of members of the family Enterobacteroaceae

Question 47

Agglutination

Answer 47

visible clumping of a particular antigen when mixed w/ antibodies specific for the particular antigen (blood group tests)

Question 48

Red Florescence

Answer 48

rhodamine D

Question 49

Yellow-Green Florescence

Answer 49

flourescein isothiocyanate

Question 50

Radioimmunoassay (RIA)

Answer 50

Uses radioisotope (iodine-125) as antibody or antigen conjugate instead of enzyme

Question 51

Enzyme Immunoassay (EIA)

Answer 51

Direct Detect Antigen (color = positive) Indirect Detect Antigen (color= positive) Competitive Detect Antigen (color= negative)

Question 52

Western Blotting

Answer 52

Detects antigens themselves or antibodies to specific antigens

Question 53

Probe Technology

Answer 53

uses complimentary bp's of probe to bind to DNA and RNA