21. The Immune System

How does the formation of an antigen–antibody complex cause the elimination of an antigen?

Mark the following statements as true or false. If a statement is false, correct is to make a true statement.

d. Vaccinations are given to induce the production of the inflammatory response.

Binding of antigens to receptors of immunocompetent lymphocytes leads to clonal selection. Describe the process of clonal selection. What nonlymphocyte cell is a central actor in this process, and what is its function?

Antibodies released by plasma cells are involved in:

a. Humoral immunity

b. Immediate hypersensitivity reactions

c. Autoimmune disorders

d. All of the above

Mark the following statements as true or false. If a statement is false, correct is to make a true statement.

Subunit vaccines consist of pathogens that are alive but unable to cause disease.

An investigator at a crime scene discovers some body fluid on the victim's clothing. The investigator carefully takes a sample and sends it to the crime lab for analysis. On the basis of the analysis of antibodies, could the crime lab determine whether the sample is blood plasma or semen? Explain.

Which antibody class is abundant in body secretions?

a. IgA

b. IgD

c. IgE

d. IgG

e. IgM

An anesthesia technician is advised that she should be vaccinated against hepatitis B, which is caused by a virus. She is given one injection and is told to come back for a second injection in a month and a third injection after 6 months. Why is this series of injections necessary?

Which of the following is NOT an organ where clonal selection occurs?