Lymphatic System

Question 1

What is the first line of defense within the innate immunity system?

Answer 1

Barrier such as the skin or muscous membranes
- prevents entry to body tissue physically

Question 2

Name the two arms of the adaptive defense system, and relate each to a
specific lymphocyte type (B or T cell).

Answer 2

It splits into humoral (B-cells) and cell-mediated immunity (T-cells)

Question 3

Define humoral immunity.

Answer 3

Defence in extracellular fluids
results in the production of antibodies (immunoglobins)

Question 4

State the role of plasma cells.

Answer 4

To secrete antibodies

Question 5

What is a lymphocyte?

Answer 5

White blood cell

Question 6

Explain the function(s) of antibodies

Answer 6

Antibodies are proteins produced by sensitised B cells or plasma cells in response to an antigen

Question 7

Describe the structure of an antibody monomer.

Answer 7

An antibody is composed of 4 polypeptide chains that form a Y shaped molecule
Variable = antigen-binding
Constant = function & class

Question 8

List the five antibody classes, and describe their specific roles in immunity.

Answer 8

Immunoglobins = IgM, IgA, IgD, IgG, & IgE

Question 9

Describe several ways in which antibodies act against antigens.

Answer 9

Aggulination, complement fixtation, neutralisation, opsonisation & precipitation

Question 10

Distinguish the roles of helper, regulatory, and cytotoxic T cells.

Answer 10

Cytotoxic = directly kill foreign or infected cells
Helper T = direct the adaptive immune response and turn on B & T cells (mac)
Regulatory = turn off immune response once foreign material is destroyed

Question 11

What is the difference between active & passive immunity?

Answer 11

Active = produced by person’s own body during infection/vaccine
Passive = when antibodies by another person is injected into bloodstream e.g. babies

Question 12

Name the functions of humoral immunity.

Answer 12

Formation of antigen & antibody inactivates the antigen and enhances phagocytosis (op.) by neutrophils by
- neutralisation (toxins, viruses)
-aggulination (cell bound antigens)
- precipitation (cell soluble)

Question 13

How are antibodies produced?

Answer 13

Antibodies (proteins) are produced from plasma cells in the lymph nodes by activated B cells in response to a specific antigen.

Question 14

Describe briefly the defense mechanisms that is directly facilitated by antibodies?

Answer 14

Neutralization of pathogens to prevent infection of host cells
Activation of the complement system
Opsonization of pathogens for destruction by phagocytes

Question 15

What are the two different types of body defences

Answer 15

Adaptive & Innate

Question 16

What is the function of lymph nodes in the lymphatic system?

Answer 16

To filter and purify lymphatic fluid

Question 17

In a routine examination, some blood is taken and analysed. The results show a high IgM titer but a lower IgG titer for the mumps virus. This would suggest that the person:

Answer 17

was recently infected with mumps

Question 18

Specific defenses depend on the activities of

Answer 18

lymphocytes

Question 19

The first line of cellular defence against pathogens is

Answer 19

phagocytes

Question 20

Which one of the following statements most accurately describes innate immunity?

Answer 20

Cell surface molecules on bacteria trigger phagocytosis and the inflammatory response, key features of innate immunity

Question 21

Antibodies recognize antigens

Answer 21

via their hypervariable regions

Question 22

Which of the following will increase lymph flow?

Answer 22

elevated cardiovascular capillary pressure

Question 23

Activation of a cytotoxic T cell results in the formation of a clone of cytotoxic T cells that consist of

Answer 23

both active cytotoxic T cells and memory cytotoxic T cells

Question 24

What is adaptive immunity characterised by??

Answer 24

Memory and specificity

Question 25

What does the innate immune system include

Answer 25

Mucous membranes and skin

Question 26

Macrophages are a type of

Answer 26

monocyte

Question 27

name all the lymphoid organs

Answer 27

spleen, peyer’s patches, thymus, tonsils

Question 28

Purpose of spleen

Answer 28

red blood cell and blood reservoir

Question 29

Purpose of Peyer’s patches

Answer 29

prevent intestinal bacteria from penetrating more deeply into the body

Question 30

What does the cortex and medulla have?

Answer 30

Cortex contains follicles of lymphocytes and medulla is full of macrophages

Question 31

What are natural killer cells

Answer 31

lymphocytes that act non specifically to lyse virus infected, malignant cells and other nonspecific targets