CHS PRACTICE EXAM CERTIFIED
HISTOCOMPATIBILITY SPECIALIST 200
QUESTIONS FINAL SCRIPT 2026 FULL
SOLUTIONS AND CORRECT ANSWERS
GRADED A+
⩥ Which of the following is not a component of the reticuloendothelial
cell system?
a. Microglial cells
b. Kupffer cells
c. Langerhans cells
d. Neutrophils
e. Monocytes. Answer: Neutrophils
Macrophages = tissue
Monocytes = blood
Kupffer cells = liver
Microgial cells = nervous system
Langerhans = skin
Not = endothelial cells, fibroblasts, and most leukocytes
⩥ Opsonization is a term to describe what?
,a. Lysis of bacteria
b. Coating of bacteria
c. Ingestion of bacteria
d. Killing of bacteria
e. Phagocytosis. Answer: Coating of bacteria
Antibody opsonization is the process by which a pathogen is marked for
ingestion and eliminated by a phagocyte.
⩥ Which of the following does not describe a role of antibodies in host
defense?
a. They serve as a bridge between bacteria and phagocytes
b. They lyse bacteria
c. They enhance complement binding to the bacterial cell wall
d. They prevent viruses from infecting cells
e. They bind pathogens in mucus secretions. Answer: They lyse bacteria
⩥ MHC Class I and II molecules differ in all of the following except
a. Types of T cells they stimulate
b. Types of cells they are expressed on
c. Which chromosome they are located on
d. Types of antigens they present
,e. Whether or not they have foreign peptides in the antigen-binding
groove. Answer: Which chromosome they are located on
⩥ The primary role of the proteasome in antigen presentation is to
a. Prevent premature folding of MHC class I molecules
b. Process cytoplasmic proteins
c. Degrade recycled MHC molecules
d. Bind HLA-DM in the endosome
e. Chaperone peptides to the cell surface. Answer: Process cytoplasmic
proteins
The main function of the proteasome is to degrade unneeded or damaged
proteins by proteolysis, a chemical reaction that breaks peptide bonds.
⩥ Peptides that bind to MHC class I molecules differ from peptides that
bind to MHC class II molecules in all
except which of the following ways?
a. They are shorter
b. They were processed by different proteases
c. They anchor in the middle instead of the end of the MHC molecule
d. They interact with different subsets of T cells. Answer: They anchor in
the middle instead of the end of the MHC molecule
, ⩥ HLA-DM is primarily involved in the
a. Activation of cytotoxic T cells
b. Loading antigen onto HLA-DR molecules
c. Preventing HLA-A molecules from folding prior to antigen binding
d. Rejection of islet grafts
e. Induction of diabetes mellitus. Answer: Loading antigen onto HLA-
DR molecules
⩥ The antigen-binding site of an antibody is comprised of which of the
following?
a. The variable region of the light and heavy chains
b. The variable region of the light chain only
c. The entire light chain
d. The entire heavy chain
e. The Fc portion of the immunoglobulin molecule. Answer: The
variable region of the light and heavy chains
⩥ The immunoglobulin that binds the most complement is
a. IgA
b. IgD
c. IgM
d. IgG2
e. IgE. Answer: IgM
HISTOCOMPATIBILITY SPECIALIST 200
QUESTIONS FINAL SCRIPT 2026 FULL
SOLUTIONS AND CORRECT ANSWERS
GRADED A+
⩥ Which of the following is not a component of the reticuloendothelial
cell system?
a. Microglial cells
b. Kupffer cells
c. Langerhans cells
d. Neutrophils
e. Monocytes. Answer: Neutrophils
Macrophages = tissue
Monocytes = blood
Kupffer cells = liver
Microgial cells = nervous system
Langerhans = skin
Not = endothelial cells, fibroblasts, and most leukocytes
⩥ Opsonization is a term to describe what?
,a. Lysis of bacteria
b. Coating of bacteria
c. Ingestion of bacteria
d. Killing of bacteria
e. Phagocytosis. Answer: Coating of bacteria
Antibody opsonization is the process by which a pathogen is marked for
ingestion and eliminated by a phagocyte.
⩥ Which of the following does not describe a role of antibodies in host
defense?
a. They serve as a bridge between bacteria and phagocytes
b. They lyse bacteria
c. They enhance complement binding to the bacterial cell wall
d. They prevent viruses from infecting cells
e. They bind pathogens in mucus secretions. Answer: They lyse bacteria
⩥ MHC Class I and II molecules differ in all of the following except
a. Types of T cells they stimulate
b. Types of cells they are expressed on
c. Which chromosome they are located on
d. Types of antigens they present
,e. Whether or not they have foreign peptides in the antigen-binding
groove. Answer: Which chromosome they are located on
⩥ The primary role of the proteasome in antigen presentation is to
a. Prevent premature folding of MHC class I molecules
b. Process cytoplasmic proteins
c. Degrade recycled MHC molecules
d. Bind HLA-DM in the endosome
e. Chaperone peptides to the cell surface. Answer: Process cytoplasmic
proteins
The main function of the proteasome is to degrade unneeded or damaged
proteins by proteolysis, a chemical reaction that breaks peptide bonds.
⩥ Peptides that bind to MHC class I molecules differ from peptides that
bind to MHC class II molecules in all
except which of the following ways?
a. They are shorter
b. They were processed by different proteases
c. They anchor in the middle instead of the end of the MHC molecule
d. They interact with different subsets of T cells. Answer: They anchor in
the middle instead of the end of the MHC molecule
, ⩥ HLA-DM is primarily involved in the
a. Activation of cytotoxic T cells
b. Loading antigen onto HLA-DR molecules
c. Preventing HLA-A molecules from folding prior to antigen binding
d. Rejection of islet grafts
e. Induction of diabetes mellitus. Answer: Loading antigen onto HLA-
DR molecules
⩥ The antigen-binding site of an antibody is comprised of which of the
following?
a. The variable region of the light and heavy chains
b. The variable region of the light chain only
c. The entire light chain
d. The entire heavy chain
e. The Fc portion of the immunoglobulin molecule. Answer: The
variable region of the light and heavy chains
⩥ The immunoglobulin that binds the most complement is
a. IgA
b. IgD
c. IgM
d. IgG2
e. IgE. Answer: IgM
