Quiz Questions Exam 1

Question 1

What is the One Health Initiative?

Answer 1

Human Health, animal health, and global health are inextricably linked

Question 2

Most emerging infectious disease outbreaks occur for what reason?

Answer 2

Humans encroach on wilderness and wildlife, changing the balance of the ecosystem

Question 3

What factors led to the increase in Lyme disease in the US?

Answer 3

Deforestation caused the loss of predators of the white-footed mouse, which is a very bad groomer, so overpopulation of infected mice led to higher rates of infected ticks and higher rates of transmission to humans

Question 4

Which factors have led to decreases in the incidence of infectious diseases?

Answer 4

Vaccines, drug development, education

Question 5

What is the primary difference between a Gram + and Gram - bacterial cell wall?

Answer 5

Gram+ has a thick peptidoglycan layer with teichoic acids and Gram- has a thin peptidoglycan layer with an outer membrane containing lipopolysaccharides

Question 6

Why do some bacteria produce spores?

Answer 6

Spores allow the bacteria to survive in a dormant state under environmentally harsh conditions.

Question 7

What are the characteristics that define a Virus?

Answer 7

• Obligate intracellular parasite

- chromosome can be RNA, DNA, segmented, and packaged inside either a naked capsid or a capsid with an envelope

Question 8

envelope or naked capsid:

- environmentally labile

Answer 8

naked

Question 9

envelope or naked capsid:

- spread easily by fomites

Answer 9

naked

Question 10

envelope or naked capsid:

- released by budding

Answer 10

enveloped

Question 11

envelope or naked capsid:

- detergents destroy infectivity

Answer 11

enveloped

Question 12

envelope or naked capsid:

- still infectious if it dries out

Answer 12

naked

Question 13

envelope or naked capsid:

- requires antibodies and cell-mediated immune response

Answer 13

enveloped

Question 14

envelope or naked capsid:

- survives the gut to cause foodborne illness

Answer 14

naked

Question 15

envelope or naked capsid:

- coated with lipids and glycoproteins

Answer 15

enveloped

Question 16

Bacterial and viruses make errors during replication, resulting in mutations in genomes.

Answer 16

• Bacteria have multiple mechanisms for genetic repair, including recombination, SOS response, and excision
• Homologous recombination is used by both bacteria and viruses to repair genetic mutations, and also gain functions such as antibiotic/antiviral resistance
• Mutation and repair mechanisms can be used to engineer bacteria and viruses for use in medical applications and as tools for research

Question 17

There are 7 steps all viruses must go through to effectively replicate. What is not a step in the replication cycle of a naked capsid virus?

Answer 17

• budding

Question 18

A lipopolysaccharide is:

Answer 18

• only gram - bacteria
• also called the O antigen
• made up of repeating polysaccharide units
• an endotoxin

Question 19

the first defensse against pathogens is

Answer 19

• physical and chemical barriers

Question 20

function of eosinophils

Answer 20

granular cells that defend against parasites by releasing peroxidase and phosphatases, and also involved in allergic response

Question 21

function of basophils or mast cells

Answer 21

granular cells that release histamine during an inflammatory or allergic response

Question 22

function of neutrophils

Answer 22

primary phagocytic defense against bacteria; these cells ingest and degrade the bacteria but do not present antigen to activate the adaptive response

Question 23

function of monocytes

Answer 23

circulating cells that differentiate into macrophages or dendritic cells in tissues

Question 24

function of dendritic cells

Answer 24

professional antigen presenting cells that phagocytose pathogens, migrate to the draining lymph node, and present antigen to naive T cells to initiate the adaptive response

Question 25

function of macrophages

Answer 25

antigen presenting cells that phagocytose pathogens, presenting antigens to T cells, and produce cytokines/chemokines to enhance the inflammatory response

Question 26

function of NK cells

Answer 26

granular lymphocytes that kill infected or tumor cells without requiring activation through a T cell receptor and MHC

Question 27

function of CD4 T cells

Answer 27

help initiate and direct adaptive immune response

Question 28

function of CD8 T cell

Answer 28

recognize and kill infected cells after activation by T helper cells

Question 29

function of plasma B cells

Answer 29

produces antibodies

Question 30

function of memory cells

Answer 30

remember a previous threat to response to a second exposure very rapidly

Question 31

during the innate response, what occurs?

Answer 31

Neutrophils phagocytose bacteria to clear the infection, macrophages phagocytose bacteria and produce cytokines/chemokines to recruit additional monocytes and neutrophils to the site, and dendritic cells phagocytose bacteria and migrate to the draining lymph node and present antigen to naive T cells to initiate the adaptive response

Question 32

What are the 3 main functions of macrophages?

Answer 32

- phagocytosis - antigen presentation - cytokine secretion

Question 33

where do dendritic cells presnt antigen to naive T cells?

Answer 33

paracortex of the lymph node or the white pulp of the spleen

Question 34

receptors on phagocytic cells recognize specific types of molecules on/in bacteria and viruses. these molecules are referred to as:

Answer 34

Pathogen Associated Molecular Patterns (PAMPs)

Question 35

What do TLRs recognize?

Answer 35

bacterial and viral DNA, ssRNA, dsRNA, flagellin, and various other molecules specifically associated with pathogens

Question 36

what are some of the factors in body secretions (tears, saliva, mucus) that have antimicrobial activity?

Answer 36

defensins, lactoferrin, immunoglobulin A

Question 37

Most cells in the body express ____ molecules containing "self" antigen unless they are infected or cancerous; if the express "non-self" bits, NK and CD8 cells will recognize and kill them. Antigen presenting cells phagocytose pathogens and express bits of the pathogen in ____ molecules to present antigen to T and B cells.

Answer 37

- MHC class I | - MHC class II

Question 38

What is the result of the acute phase response?

Answer 38

fever, metabolic changes, and activation of the complement system

Question 39

the lymph nodes and spleen have similar purposes, but the spleen has an additional purpose. What functions do the have in common and what additional function does the spleen have?

Answer 39

both filter antigens from host fluids, facilitate antigen presentation to naive T cells and B cell activation, and the formation of germinal centers, but the spleen also filters old blood cells from the blood and recycles them

Question 40

branch of the immune response: | - targets extracellular pathogens

Answer 40

humoral

Question 41

branch of the immune response: | - targets intracellular pathogens

Answer 41

cell-mediated

Question 42

branch of the immune response: | - targets all types of pathogens the same way

Answer 42

innate

Question 43

branch of the immune response: | - characterized by inflammation, acute phase response, complement, and interferons

Answer 43

innate

Question 44

branch of the immune response: | - characterized by B cell production of antibody

Answer 44

humoral

Question 45

branch of the immune response: | - characterized by CD8 T cell, NK T cell and macrophage-induced killing

Answer 45

cell-mediated

Question 46

the process through which B cells improve their affinity for their cognate antigen is called ___

Answer 46

somatic hypermutation

Question 47

the process through which B cells change the base portion (Fc portion) of their antibody (to IgA, IgE, or IgG) after encountering an antigen is called ___

Answer 47

class switching

Question 48

A particular B cell that is activated independently of Th cells would secrete what type of antibody in response to an infection.

Answer 48

IgM

Question 49

What are 3 mechanisms used by CTLs to kill their target cells?

Answer 49

- directly killing the target cell by releasing granzyme B and perforin - Inducing apoptosis in the target by releasing TNF-alpha and IFN-gamma - inducing apoptosis by Fas-FasL interactions with the target cell

Question 50

antibody component/function | - binds antigen

Answer 50

variable region

Question 51

antibody component/function | - binds to receptors on cells to faciliate phagocytosis

Answer 51

Fc region

Question 52

antibody component/function | - goes through somatic hypermutation

Answer 52

variable region

Question 53

``` antibody component/function - goes through class switch recombination ```

Answer 53

Fc region

Question 54

Th1 / Th2 | - CTLs

Answer 54

Th1

Question 55

Th1 / Th2 | - macrophages

Answer 55

Th1

Question 56

Th1 / Th2 | - IL4

Answer 56

Th2

Question 57

Th1 / Th2 | - IL5

Answer 57

Th2

Question 58

Th1 / Th2 | - Extracellular pathogens

Answer 58

Th2

Question 59

Th1 / Th2 | - intracellular pathogens

Answer 59

Th1

Question 60

Th1 / Th2 | - IFN-gamma

Answer 60

Th1

Question 61

Th1 / Th2 | - allergies

Answer 61

Th2

Question 62

Th1 / Th2 | - antibodies

Answer 62

Th2