Exam 3- Immune

Question 1

Describe skin according to the immune system.

Answer 1

tightly packed cells are difficult to penetrate; shedding removed attached microbes; dryness inhibits growth of many species

Question 2

Describe mucous membranes.

Answer 2

lines gastrointestinal, respiratory, & genitourinary tracts, secrete mucus, contain cilia

Question 3

What is mucus?

Answer 3

viscous glycoprotein produced by goblet cells, traps microbes, also contains other secreted compounds like lysozyme

Question 4

What does lysozyme do?

Answer 4

targets the cell wall of bacteria

Question 5

What does the ciliary escalator do?

Answer 5

transports microbes trapped in mucus away from the lungs towards throat

Question 6

What is phagocytosis?

Answer 6

the ingestion of microbes or particles by a cell (called a phagocyte)

Question 7

What do phagocytes include?

Answer 7

neutrophils, macrophages fixed in lungs, liver, other tissues

Question 8

What do free (wandering) macrophages do?

Answer 8

move to sites of infection

Question 9

Microbes possess unique structures called ________ ______ _______ (MAMPs) that are recognized by ______ ______ (TLRs) & other receptors present on host cells.

Answer 9

microbe-associated molecular patterns, Toll-like receptors

Question 10

What does binding of MAMPs by host cell receptors activate?

Answer 10

stimulates phagocyte to release cytokines that attract other phagocytes to site of infection, initiate phagocytosis

Question 11

Examples of MAMPs.

Answer 11

flagellin, peptidoglycan, lipopolysaccharide (LPS)

Question 12

What is the bubonic plagues causative agent?

Answer 12

Yersinia pestis

Question 13

In the resulting phagolysosome, microbial cells are attacked by ______ & ______

Answer 13

digestive enzymes & toxic oxygen products

Question 14

What does opsonization enhance?

Answer 14

phagocytosis

Question 15

What is opsonization?

Answer 15

the coating of a microbe by host proteins to enhance phagocytosis by promoting attachment of microbes to phagocyte

Question 16

2 examples of opsonins.

Answer 16

antibodies & complement proteins

Question 17

What is innate (nonspecific) immunity?

Answer 17

physical & chemical barriers to infection, nonspecific responses to destroy invading cells, present at birth

Question 18

What is adaptive immunity?

Answer 18

reaction to specific pathogens- parts of foreign proteins, sugars, molecules
memory component- faster response if exposed a second time

Question 19

What are antigens?

Answer 19

“antibody generating” macromolecule that interacts with the immune system

Question 20

What is the epitope?

Answer 20

a specific binding site on an antigen (antigens can have more than one)

Question 21

What are haptens?

Answer 21

very small molecules that, when attached to a larger carrier protein, can act as an antigen

Question 22

Describe antibodies.

Answer 22

immunoglobulins (Ig), made by the host in response to a specific antigen, & can recognize & bind to a specific antigen

Question 23

What are the 5 classes of antibodies?

Answer 23

1. IgG
2. IgM
3. IgA
4. IgD
5. IgE

Question 24

Explain humoral immunity.

Answer 24

B cells (B lymphocytes) produce antibodies that directly target antigens. attacks extracellular threats

Question 25

Explain cell-mediated immunity.

Answer 25

activated T cells (T lymphocytes) control antibody production & can directly kill infected host cells, attacks infected cells

Question 26

Where are B cells produced.

Answer 26

in bone marrow

Question 27

Where do B cells have antibodies?

Answer 27

on the cell surface

Question 28

When does the B cell become activated?

Answer 28

when the surface antibodies bind their specific epitope

Question 29

What do activated B cells divide & differentiate into?

Answer 29

plasma cells & memory cells

Question 30

What do plasma cells do?

Answer 30

produce hundreds to thousands of antibodies per second

Question 31

What are memory cells responsible for?

Answer 31

rapid, enhanced immune response after later exposure to same antigen

Question 32

When does primary response occur?

Answer 32

after initial contact with antigen

Question 33

When does secondary (memory) response occur?

Answer 33

after second exposure

Question 34

What can B cells be activated by?

Answer 34

T-dependent antigens or T-independent antigens

Question 35

What are T-dependent antigens?

Answer 35

antigen presented with MHC II to TH cell

Question 36

What do T-independent antigens do?

Answer 36

stimulate the B cell to make antibodies without T-helper cells

Question 37

What do T-independent antigens have?

Answer 37

repeating units (epitopes) that can bind multiple antibodies on surface of B cell- capping of the B cell

Question 38

T-independent antigens have weak/no _____ ______ _______

Answer 38

memory cell production

Question 39

What are humoral antibodies effective against?

Answer 39

circulating pathogens

Question 40

What to plasma cells do?

Answer 40

produce antibodies that bind to bacteria/viruses/toxins on outside of cell

Question 41

Explain Major Histocompatibility Complex (MHC) class I.

Answer 41

found on nucleated cells, markers of "self", found in human cells & is protected against our immune system so they don't get destroyed

Question 42

Explain MHC class II.

Answer 42

found on antigen presenting cells like B cells

Question 43

Describe Helper T cells (TH cells)

Answer 43

surface glycoprotein CD4, CDY bind to MHC class II molecules on B cells & other Antigen Present Cells

Question 44

What do helper T cells assist with?

Answer 44

activation of B cells & other T cells

Question 45

Describe Cytotoxic T cells (Tc Cells)

Answer 45

surface glycoprotein CD8, CD8 binds to MHC class I molecules,

Question 46

What to Tc cells differentiate into?

Answer 46

cytotoxic T lymphocyte (CTL)

Question 47

What do Tc cells do?

Answer 47

destroy bacteria & infected host cells (kills)

Question 48

What do vaccines stimulate?

Answer 48

the body's immune system to respond to a specific pathogen

Question 49

What is a vaccine?

Answer 49

a suspension of organisms or fractions or organisms that is used to induce immunity

Question 50

No vaccines for _______ diseases.

Answer 50

fungal

Question 51

When attenuated or killed pathogens or fragments of the pathogen are used what happens?

Answer 51

usually do not cause disease, trigger immune response, induce memory cells

Question 52

What are attenuated whole-agent vaccines

Answer 52

-live, attenuated microbe -microbe can be weakened by multiple passage in the lab -lifelong immunity -can "back mutate: to virulent pathogen

Question 53

Example of attenuated whole-agent vaccines.

Answer 53

Measles, mumps, rubella (MMR) vaccine

Question 54

What are inactivated whole-agent vaccines?

Answer 54

-microbe killed or inactivated by heat, chemical, or radiation -safer than live vaccines -less effective; often require booster doses

Question 55

Examples of inactivated whole-agent vaccines.

Answer 55

raboes, flu, polio (Salk polio vaccine)

Question 56

What are toxoid vaccines?

Answer 56

- some diseases are caused by bacterial toxins -toxoids are INACTIVE toxins -require booster shots

Question 57

Examples of toxoid vaccines.

Answer 57

tetanus, diphtheria

Question 58

What are subunit vaccines?

Answer 58

-antigenic fragments of pathogen that best stimulates immune response -safe -recombinant vaccines produced using recombinant technology

Question 59

Example of subunit vaccines.

Answer 59

Hepatitis B

Question 60

What are conjugated vaccines?

Answer 60

-large polysaccharides can be T-independent antigens; result in weak immune response & no memory cells -polysaccharide conjugated with more antigenic proteins results in better immunization

Question 61

Example of conjugated vaccines.

Answer 61

Haemophilus influenzae type B (hib)

Question 62

What are nucleic acid vaccines?

Answer 62

-DNA or RNA encoding pathogen protein injected into patient; patient produces antigen that stimulates patient production of antibodies -protein antigens, not polysaccharides