Humoral Immunity

Question 1

The process begins when B cells encounter antigens, which are usually proteins or other molecules on the surface of pathogens (such as bacteria or viruses).

Answer 1

Antigen Recognition

Question 2

B cells internalize the antigens and present fragments of them on their cell surface using a molecule called Major Histocompatibility Complex II (MHC II

Answer 2

Antigen Presentation

Question 3

Helper T cells recognize the antigen-MHC II complex and release chemical signals (cytokines) that __________.

Answer 3

Activate B Cells

Question 4

The activated B cell undergoes __________, where it divides and produces identical copies (clones) of itself. Some of these cells differentiate into plasma cells,
while others become memory B cells

Answer 4

Clonal Selection

Question 5

Plasma cells are specialized B cells that produce antibodies. These antibodies are proteins that can specifically bind to the antigen that initiated the immune response

Answer 5

Plasma Cell Differentiation

Question 6

Plasma cells release large quantities of antibodies into the bloodstream. Antibodies circulate throughout the body and bind to antigens, marking them for destruction or neutralization by other components of the immune system

Answer 6

Antibody Production

Question 7

Antibodies have various functions, including:
▪ ___________: Blocking the harmful effects of toxins or pathogens.
▪ ___________: Marking pathogens for phagocytosis by macrophages or neutrophils.
▪ ___________: Triggering the complement system, leading to the destruction of the
pathogen.
▪ ________: Clumping together of pathogens for easier removal by immune cells.

Answer 7

Neutralization
Oposonization
Complement Activation
Agglutination

Question 8

Some of the activated B cells become __________, which persist in the body for an extended period. These cells “remember” the specific antigen and facilitate a faster and more robust response upon re-exposure to the same pathogen

Answer 8

Memory B Cells

Question 9

The presence of memory B cells provides long-term immunity. If the individual encounters the same antigen in the future, memory B cells quickly differentiate into plasma cells, producing a rapid and heightened antibody response

Answer 9

Long-term Immune Memory