Sentization

Question 1

During B cells sensitization, antigens are:

Answer 1

 Taken into the B cell
 Processed
 Reappear on surface, bound to Class II MHC protein

Question 2

How do Helper T cells help sensitized B cells?

Answer 2

Sensitized B cell is prepared for activation but needs helper TH2 cell that
are activated by same antigen

Question 3

 Helper T cell binds to MHC complex on the B cell
 Secretes cytokines that promote B cell activation and division

Answer 3

What happens with B cells during activation? What do helper T cells do?
B cell activation

Question 4

 Antibody Structure
 Two parallel pairs of polypeptide chains
 One pair of heavy chains
 One pair of light chains: Each chain contains

Answer 4

 Constant segments
 Variable segments

Question 5

What are the five classes of immunoglobulins (Igs)

Answer 5

 IgG, IgD, IgE, IgM, IgA
 Are found in body fluids
 Are determined by constant segments
 Variable segment remains the same
 Have no effect on antibody specificity

Question 6

T lymphocyte-derived cytokines,
which direct B lymphocytes to
switch to specific Ig classes.

Answer 6

Isotype switching is controlled by

Question 7

IgG antibody

Answer 7

largest and most diverse class of antibodies
 80 percent of all antibodies
 IgG antibodies are responsible for resistance against viruses, bacteria, and bacterial toxins
- can cross the placenta, and maternal IgG provides passive immunity to fetus during embryological development

Question 8

IgE

Answer 8

• important in the allergic response
  -release histamine and other chemicals that accelerate
  inflammation in the immediate area

Question 9

In B cells, the function of IgD is to

Answer 9

signal the B cells to be activated.

Question 10

IgM is the first class of antibody secreted after an antigen is _______

Where do they originate from

Answer 10

• The first class of antibody secreted after an antigen is
  encountered, they originate from the spleen

-
polymerizes and circulates as a five-antibody starburst

Question 11

IgA is found primarily in

Answer 11

• glandular secretions such as mucus, tears, saliva, breast milk
• Attack pathogens before they gain access to internal tissues
• Immunoglobulin A (IgA) is the first line of defense in the resistance against
  infection, via inhibiting bacterial and viral adhesion to epithelial cells and
  by neutralization of bacterial toxins and virus, both extra- an

Question 12

cytokine storm is an

Answer 12

-overreaction of the body’s immune system

COVID-19, the immune system releases cytokines, into the bloodstream out of proportion to the threat or long after the
virus is no longer a threat

Question 13

 Infant immunity

Answer 13

-develops at 5-6 weeks in utero, is well-developed at birth, and matures rapidly in the post-natal period

 Trans-placental immunity via IgG for benefit of newborn
 Breast-feeding provides passive immunity via IgA

Question 14

 Thymus shrinks reducing number
of T-cells numbers
 Cytokine production slows
 Lymphocytes become less
responsive
 More prone to autoimmune
reaction

Answer 14

Aging and immunity: effects not
fully understood