Micro Ch. 15

Question 1

What is the third line of defense?

Answer 1

Specific Immunity

Question 2

How is specific immunity different from the first 2 lines of defense?

Answer 2

It is not innate, but adaptive. It is only acquired after an immunizing event such as an infection or immunization.

Question 3

What is immunity?

Answer 3

The resistance developed after contracting childhood ailments that provides long-term protetion against future attacks.

Question 4

What is immunocompetence?

Answer 4

The ability of the body to react with countless foreign substances.

Question 5

What is an antigen/immunogen?

Answer 5

Molecules that stimulate a response by B and T cells. Usually protein or polysaccharide molecules on or inside all cells and viruses.

Question 6

What 2 features most characterize the third line of defense?

Answer 6

Specificity and memory

Question 7

What is the property of memory?

Answer 7

Refers to the rapid mobilization of lymphocytes that have been programmed to “recall” their first engagement with an invader and rush to attack if it becomes present again.

Question 8

What are the 4 stages of specific immunity?

Answer 8

1) Lymphocyte development and differentiation
2) The Presentation of antigens
3) Challenge of B and T cell lymphocytes by antigens
4. 1) B-lymphocyte response: production and activites of anitbodies
4. 2) T-lymphocyte response: cell-mediatied immunity

Question 9

Where do B cells mature?

Answer 9

Specialized bone marrow sites

Question 10

Where do T cells mature?

Answer 10

In the thymus

Question 11

What are antigen-presenting cells?

Answer 11

Macrophages or dendrites that process and present antigens to T cells in a lymphoid organ.

Question 12

What are the 3 types of T cells and their functions?

Answer 12

1) helper- activate macrophages, assist B-cell processes and help activate cytotoxic T cells
2) regulatory- control T-cell response
3) cytotoxic- lead to the destruction of infected host cells and other “foreign” cells

Question 13

Do T cells produce antibodies?

Answer 13

No

Question 14

What are the main functions of cell markers/receptors?

Answer 14

1) attachment to nonself or foreign antigens
2) binding to cell surface receptors that indicate self (MHC molecules)
3) receiving and transmitting chemical messages to coordinate the response
4) aiding in cellular development

Question 15

What is the MHC?

Answer 15

Major histocompatibility complex- a set of genes that code for human cell receptors, gives rise to a series of glycoproteins found on all cells except red blood cells, plays a vital role in recognition of self by the immune system and in rejection of foreign tissue.

Question 16

What are the 3 types of MHC?

Answer 16

Class I
Class II
Class III

Question 17

How do Class I MHC genes work?

Answer 17

They code for markers that appear on all nuclated cells =. They display unique characteristics of self and allow for the recognition of self molecules and regulation of immune reactions.

Question 18

How do Class II MHC genes work?

Answer 18

They code for immune regulatory markers found on macrophages, dendritic cells, and B cells. They are involved in presenting antigens to T cells during cooperative immune reactions.

Question 19

How do B cells mature?

Answer 19

They mature on certain bone marrow sites called stromal cells. These cells nurture stem cells and provide chemical signals that initiate B-cell development. Hundereds of millions of distinct B-cells are able to develop due to gene modification and selection.

Question 20

How do T cells mature?

Answer 20

Their maturation and development of their specific receptors are directed by the thymus gland and its hormones.

Question 21

What is a epitope?

Answer 21

The primary signal that a molecule is foreign. A difference in molecule shape on an antigen.

Question 22

What are the steps of a B cell response?

Answer 22

1) Binding of epitope
2) Anitgen processing and presentation
3) B-cell/T-cell recognition and cooperation
4) B-cell activation
5) Clonal expansion
6) Regulatory B-cell activity
7) Antibody production and secretion

Question 23

What is opsonization?

Answer 23

A processin which specific microorganisms of other particles are coated iwth specific antibodies so that they will be more readily recognized by phagocytes.

Question 24

What are the outcomes of antigen-antibody interaction?

Answer 24

Agglutinazation
Neutralization
(also an antitoxin can be activaed which neutralizes bacterial exotoxins)

Question 25

What are the 5 types of antibodes?

Answer 25

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

Question 26

List the antibodies in order from most abudant to least.

Answer 26

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

Question 27

What are the 3 types of T cells?

Answer 27

1) T helper
2) T regulatory
3) T cytotoxic

Question 28

What is the function of T helper cells?

Answer 28

Activate the cell-mediated immune pathway, secretes tumor necrosis factor and interferon gamma, responsible for delayed hypersensitivity, drive B-cell proliferation and promotes inflammation.

Question 29

What is the funciton of T regulatory cells?

Answer 29

Controlsspecific immune response. prevents autoimmunity.

Question 30

What is the funciton of T cytotoxic cells?

Answer 30

Destroys a target foreign cell by lysis. important in destructin of complex microbes, cancer cells, virus-infected cells, graft rejection. Requires MHC-I for function.

Question 31

What is the function of memory cells?

Answer 31

Remain in serum for a relatively long time, is programmed to react rapidly with its antigen.

Question 32

What are the 4 specific descriptors of specific immune state?

Answer 32

1) Natural Active- person develoes their own response to a microbe
2) Artifical Active- a person devlopes an immune response through immunization
3) Natural Passive- one person receives preformed immunity made by another person (breast feeding)
4) Artifical Passive- one person recevies immunity from an artifical source

Question 33

What are the principles of vaccine preparation?

Answer 33

antigen selection, effectiveness, ease in administration, safety. cost

Question 34

What is vaccination?

Answer 34

Exposing a person to material that is antigenic, but not pathogenic

Question 35

What are the 2 types of vaccines?

Answer 35

Live (attenuated)- flu

Killed ( inactivated)- Polio

Question 36

What is herd immunity?

Answer 36

Individuals immune to a communicable infectiontious disease will nto harbor it, thus reducing that occurrence of that pathogen. Effetive in protecting those who are unable to vaccinate like those with and allergy or the very young.

Question 37

What is a toxoid?

Answer 37

Used in vaccines, a toxin that has been rendered non-toxic, but is still capable of stimulating the production of antibodies.

Question 38

What is neutralization?

Answer 38

Antibodies fill the surface receptors on a virus or the active site on a microbial enzyme to prevent it from attaching normally.