Immune System Physiology - Q&A

Question 1

Define innate immunity

Answer 1

Non-specific host defences that exist pior to exposure to an antigen

Question 2

Innate immunity involves all of the following except:
A Physical barriers
B Phagocytosis
C Inflammation
D Antibody production

Answer 2

D Antibody production

Question 3

Name one physical barrier that prevent the entry of pathogens in our body.

Answer 3

Epidermis, gastric secretion, lysozyme, host microbiome, mucous membranes…

Question 4

What cells would be most active in early, antiviral immune responses the first time one is exposed to pathogen?

Answer 4

NK cells

Natural killer cells

Question 5

Name one cell type with phagocytic activity

Answer 5

Macrophage

Neutrophil

Question 6

Which of the following cells is important in the innate immune response?
A B cells
B T cells
C macrophages
D plasma cells

Answer 6

C macrophages

Question 7

What are the four steps/phases of an inflammatory reaction?

Answer 7

Recognition, Recruitment, Removal, Resolution

Question 8

Patten recognition receptors PRR can:
A bind to conserved features of invading microbes
B recognize injured cells of the host
C mediate the synthesis of cytokines
D mediate phagocytosis
E all of the above

Answer 8

E all of the above

Question 9

Acute inflammation characteristically involves:
A Constriction of arterioles.
B Enlargement of endothelial cell
C The formation of scar tissue
D Influx of neutrophils.

Answer 9

D Influx of neutrophils.

Question 10

What are the effect of acute inflammation on the surrounding blood vessels?

Answer 10

Increased permeability of capillaries, activation of endothelial cells, vasodilatation

Question 11

What are the characteristic signs of inflammation?

Answer 11

Pain, redness, swelling, heat

Question 12

Which of the following leads to the redness of inflammation?
A increased vascular permeability
B anaphylactic shock
C increased blood flow
D recruitment of neutrophils

Answer 12

C increased blood flow

Question 13

The movement of phagocytes in the direction of an infection, due to attraction by complement, chemicals released by microorganisms, and the remnants of damaged cell membranes is a process called:
A phagocytosis.
B chemotaxis.
C adherence.
D tolerance

Answer 13

B chemotaxis.

Question 14

Name one function of the complement system

Answer 14

Opsonisation, increase inflammation, cell lysis

Question 15

Which of the following is NOT TRUE with regard to complement?
A It damages plasma membranes of foreign cells.
B It is involved in the development of inflammation.
C It can bind to the surface of microbes and promote phagocytosis.
D It is an immune process that is specific to the invading microbe.
E It is a cascade pathway

Answer 15

It is an immune process that is specific to the invading microbe.

Question 16

All of the following are true regarding inflammation EXCEPT:
A The same sequence of events occurs in response to any injury, whether it be a burn, an infection, or trauma.
B The signs of inflammation are pain, redness, swelling, heat, and possibly loss of function.
C Cytokines, histamine, complement and other chemical mediators are released.
D Monocytes are the first cells to arrive from the bloodstream at the site of inflammation.
E The purpose of inflammation is to remove foreign invaders and heal the damaged tissue

Answer 16

D Monocytes are the first cells to arrive from the bloodstream at the site of inflammation.

Question 17

Which process stimulate macrophages to develop a anti-inflammatory phenotype?

Answer 17

Efferocytosis

Question 18

What are the phases of tissue healing?

Answer 18

1. Hematoma formation
2. Inflammation
3. Repair
4. Remodeling

Question 19

What is the name of muscle stem cells?

Answer 19

Satellite cells

Question 20

Name at least one feature of the adaptive immune response.

Answer 20

Memory
Slow response
Specificity
Self-recognition

Question 21

Which cells are involved specifically in adaptive immunity?

Answer 21

Lymphocytes B and T

Question 22

The majority of antigens are: 
A Proteins
B Carbohydrates
C Nucleic acids
D Lipids

Answer 22

A Proteins

Question 23

Define clonal expansion

Answer 23

Lymphocytes that are able to recognize the antigen undergo rapid mitotic division.

Question 24

Why is clonal expansion so important?
A to select for specific cells
B to secrete cytokines
C to kill target cells
D to increase the numbers of specific cells

Answer 24

D to increase the numbers of specific cells

Question 25

What is the function of plasma cells?

Answer 25

Produce and secrete antibodies

Question 26

How do antibodies help clearing antigens?

Answer 26

Neutralization Agglutination Opsonization

Question 27

``` Foreign antigens phagocytosed by dendritic cells are presented by: A class I MHC molecules to cytotoxic T cells. B class II MHC molecules to helper T cells. C class I MHC molecules to helper T cells. D class II MHC molecules to cytotoxic T cells. ```

Answer 27

B class II MHC molecules to helper T cells.

Question 28

Which type of T cell lyses cells that have been infected with viruses?

Answer 28

cytotoxic T cells

Question 29

Memory cells: A produce chemokines B are responsible for passive immunity C prevent an animal from encountering certain antigens D provide an accelerated immune response upon second exposure to a particular antigen

Answer 29

D provide an accelerated immune response upon second exposure to a particular antigen

Question 30

``` Which of the following is not a mechanism by which diversity is generated for antibody synthesis? A VDJ recombination B Somatic hypermutation C Clonal expansion D Combination of heavy and light chain ```

Answer 30

C Clonal expansion

Question 31

What is the biological interest in having VDJ recombination?

Answer 31

Creation of a multitude of receptors from a limited amount of genes, giving the possibility to recognize virtually any antigen.

Question 32

What is positive selection in the development of thymocytes?

Answer 32

T cells recognizing MHC molecules receive survival signals.

Question 33

In T-cell development, negative selection is an important process for: A killing self-reacting thymocytes B killing thymocytes not recognizing self-MCH proteins C killing thymocytes that didn't rearranged correctly their TCR D killing mature T-cells that recognize self antigens after they left the thymus

Answer 33

A killing self-reacting thymocytes

Question 34

Where do B-cells mature?

Answer 34

Bone marrow

Question 35

Define self-tolerance.

Answer 35

Unresponsiveness of the immune system to self-antigens

Question 36

``` Loss of self-tolerance can lead to: A Immune deficiency B Allergies C Cancer D Autoimmune disease ```

Answer 36

D Autoimmune disease

Question 37

``` Which of the following class of pathogens consists of only unicellular organisms? A Viruses B Bacteria C Fungi D Parasites ```

Answer 37

B Bacteria

Question 38

``` Which of the following are intracellular pathogens? Viruses Bacteria Fungi Parasites ```

Answer 38

Viruses

Question 39

Name the primary lymphoid organs

Answer 39

Bone marrow | Thymus