This chapter should help the student to:
- Know the functions of the lymphoid system.
- Know the names, locations, and functions of the cells, tissues, and organs of the lymphoid system and identify them, as well as their components, in a micrograph.
- Know the distinguishing features of the lymphoid organs.
- Distinguish between central and peripheral lymphoid organs.
- Distinguish between cell-mediated and humoral immunity.
- Describe lymphocyte differentiation from stem cells to T or B memory and effector cells.
- Know the five immunoglobulin classes and their distinguishing features.
- Describe the steps in lymphocyte activation by antigens.
- Describe antigen disposal by cell-mediated and humoral mechanisms.
- Describe the path taken by lymph as it flows through the lymph nodes.
- Describe blood flow through the spleen according to the open and closed theories of circulation.
1. Describe the general structure of lymphoid tissue in terms of the:
Type of connective tissue that makes up the stroma (I.A)
Types of cells and fibers that make up the stroma (III.D.1 and 2)
Types of cells suspended within the spaces of the stroma (I.A)
Lymphoid organ in which the composition of the stroma differs from that of all other lymphoid tissues and organs (III.D.1 and 2)
2. Compare cellular and humoral immunity in terms of the:
Type of lymphocyte (B or T) primarily associated with each (I.D.1 and 2)
Requirement for direct lymphocyte contact during antigen disposal (I.D.1 and 2)
Names of the effector cells involved in each type (I.F.4; III.A.1 and 2)
3. Compare the central and peripheral lymphoid organs (I.B) in terms of the organs that comprise each group and the antigen dependence or independence of lymphocyte proliferation within them.
4. Sketch an IgG molecule (Fig. 14–1; II.A.1–6) and label the light and heavy chains, Fc and Fab fragments, constant and variable regions, and cell-binding and antigen-binding regions.
5. List the five types of immunoglobulins (Igs) secreted by plasma cells, and indicate which Ig is described by each of the following characteristics:
Most abundant in blood (II.B.1)
Can cross the placenta (II.B.1)
Secretory form consists of two Igs, protein J, and a transport component (II.B.2)
Predominant Ig in secretions (e.g., mucus, tears, saliva; II.B.2)
Usually exists as a pentamer (II.B.3)
Most effective in activating the complement system (II.B.3)
Fc portion has a great affinity for the surface of mast cells and basophils (II.B.4)
Is the primary mediator of allergic reactions (II.B.4)
Is least understood (II.B.5)
Are found on the surface of B lymphocytes (list two; II.B.3 and 5)
6. Indicate the order in which both T and B lymphocytes undergo the following processes after encountering an antigen (I.F.3 and 4):
Differentiation into effector and memory cells
Blast transformation (formation of immunoblasts)
Clonal expansion (proliferation)
7. List the T-lymphocyte effector cells and describe the basic functions of ...