Pathogenic Microbiology Test 2

Front 1

What are the general barriers of the host and what do they prevent against?

Back 1

Physical and chemical barriers, such as the skin and its slightly acidic nature. They prevent entry of the pathogen.

Front 2

What is innate immunity of the host and what does it prevent against?

Back 2

Broad pattern recognition, prevents against infection

Front 3

What is adaptive immunity and what does it prevent against?

Back 3

Antigen specific, prevents against disease.

Front 4

What are some specific physical and chemical barriers that prevent against pathogenic entry?

Back 4

skin, mucous membranes, respiratory tract, tears, intestinal tract, genitourinary tract, lysozyme, skin, cilia, acidic environment on skin and in stomach.

Front 5

What is the difference between the innate response and the adaptive response?

Back 5

The innate response is rapid and not antigen specific, whereas the adaptive response is slow, antigen specific, and has memory.

Front 6

Describe the four steps in the innate response to pathogenesis.

Back 6

1. pattern recognition and phagocytosis.
2. Inflammation.
3. Fever
4. Detect and destroy infected host cells.

Front 7

What are the three cells involved in pattern recognition and phagocytosis used in the innate response?

Back 7

dendritic cells, macrophages, and neutrophils.

Front 8

Describe the relevance of Toll-Like Receptors and what type of immunity it's related to.

Back 8

Toll-like receptors (TLR) recognize Pathogen Associated Molecular Patterns (PAMPs) on the surface of pathogens and then destroy them. termed "Broad Pattern Recognition" of the innate immune response.

Front 9

What is the result of phagocytosis?

Back 9

Cytokines and chemokines are released, which attract more phagocytes and cause inflammation and fever.

Front 10

What is the complement system?

Back 10

Proteins circulating in the serum that interact with bacteria and cause a cascade of events That cause complement fixation.

Front 11

What three events occur during complement fixation?

Back 11

Opsonization, Inflammation, Lysis.

Front 12

What happens during opsonization of complement fixation?

Back 12

Complement C3b coats the bacteria so it enhance phagocytosis.

Front 13

What happens during inflammation of complement fixation?

Back 13

Complement proteins C3a and C5a attract phagocytes to the site of infection.

Front 14

What happens during lysis of complement fixation?

Back 14

Complement proteins form a membrane attack complex. this forms holes in the bacterial membrane.

Front 15

What is inflammation and what happens during inflammation?

Back 15

localized response to injury or infection. Redness, heat, swelling, pain. Vasodilation. Phagocytes are recruited.

Front 16

What is the purpose of inflammation?

Back 16

Pathogen confinement, pathogen destruction, tissue repair.

Front 17

What is a fever and what is its purpose?

Back 17

A systemic response to infection where the body temperature is raised. this limits pathogen growth and enhaces immune activity.

Front 18

What is the difference between the two classes of MHC molecules?

Back 18

MHC class I are present in all nucleated cells and MHC class II are only present in antigen presenting cells. But all MHC molecules display fragments of protein antigen on their cell surface.

Front 19

Describe the role of MHC class I.

Back 19

Host cells normally display self-antigen, it's what prevent the immune system from killing itself. But, when a cell has been invaded it can do one of two things:
1. Display the antigen from MHC class 1.
2. Not express MHC class 1, thusly being killed by NK cells.

Front 20

What are the three antigen presenting cells?

Back 20

Macrophages, Dendritic cells, B cells

Front 21

Describe how the antigen presenting cells (APCs) work.

Back 21

internalize and process antigens from pathogens and present it to T-cells. Then APCs present the antigens to the CD4 T-cells in association with the MHC class II.

Front 22

Describe the role of CD4 T-cells.

Back 22

Activated by APCs presenting antigen in association with MHC class II. Known as "T-helper" cells. They direct and control the immune response.

Front 23

Describe the cell-mediate response.

Back 23

Enhances inflammation, activates macrophages, (makes them better killers, intracellular pathogesn may survuve within unactivated macrophages) Cytotoxicity (cytoxic CB8 T cells)

Front 24

What are the CD8 T cells?

Back 24

Once activiated, the CD8 T-cells kill host cells that display the antigen in association with MHC class I.

Front 25

What are memory T cells?

Back 25

They are long lived cells that quickly respond to the antigen in the future. This memory is what makes the immune system adaptive.

Front 26

What happens during the humoral response?

Back 26

Stimulation of antibody production, which are effective against extracellular pathogens and toxins.

Front 27

What are the parts of the antibody structure, and what do they do?

Back 27

Fab binds to the antigen and Fc interacts with the cell.

Front 28

What are the mechanisms of action of the antibody?

Back 28

neutralization, agglutination, opsonization, and lysis.

Front 29

What is a plasma cell?

Back 29

A B cell that produces large amount of antibodies.

Front 30

Where are antibodies found on a B cell?

Back 30

On the surface.

Front 31

What are the five different types of antibodies?

Back 31

IgD, IgM, IgA, IgG, and IgE.

Front 32

Describe the IgD antibody.

Back 32

Expressed on the surface of B cells.

Front 33

Describe the IgM antibody.

Back 33

First antibody produced, activates complement.

Front 34

Describe the IgG antibody.

Back 34

Activates the complement (classical pathway, opsonization, and responsible for neonatal immunity.

Front 35

Describe the IgA antibody.

Back 35

Found in mucosal membranes.

Front 36

What is isotype switching?

Back 36

switching from IgM to another class of antibody. Necessary for a strong immune response.

Front 37

What is an antigen?

Back 37

Recognized by a specific antibody or T cell, causes adaptive immune response. A pathogen has several antigens.

Front 38

What is an epitope?

Back 38

The specific molecular structure of an antigen that reacts with the antibody or T-cell. An antigen typically has several epitopes.

Front 39

What are cytokines?

Back 39

Chemical messengers that enable communication between immune cells. Serve to stimulate and regulate the immune response. Chemkines are a subset that attract other immune cells to the site of the infection.

Front 40

What are PAMPs?

Back 40

Molecular patterns on the surface of bacteria that are recognized phagocytes. for example, lippopolysaccharide and glycoprotein.

Front 41

What are antigen presenting cells?

Back 41

Cells that present antigen to the T cells. They include: Macrophages, dendritic cells, and B cells.

Front 42

What are macrophages?

Back 42

phagocytic cell, garbage collector. Cleans up debris and dead cells as well as potential pathogens. Recognizes PAMPs.

Front 43

What are neutrophils?

Back 43

Phagocytic cells that recognize PAMPs. They are the most abundant white blood cells and therefore cause pus in an infection.

Front 44

What are dendritic cells?

Back 44

APCs, they sample antigens in the environment, When they find a foreign antigen the stop sampling and take the antigen to present it to the T cells.

Front 45

What is a T cell?

Back 45

Lymphocyte that specifically recognizes protein antigens.

Front 46

What is a B cells?

Back 46

primary function is to make antibody. when activated, they differentiate into plasma cells, or antibody factories.

Front 47

Describe adaptive immunity.

Back 47

Specific and delayed, directed against a specific pathogen, and humoral or cell-mediated.