THE B LYMPHOCYTES

Question 1

Precursor cells in antibody production

Answer 1

B cells

Question 2

THE PRECURSOR OF PLASMA CELLS

Answer 2

B cells

Question 3

The pro-B cell has distinctive markers that include surface antigens

Answer 3

CD19, CD45R, CD43, CD24, and c-Kit

Question 4

Cell progenitors

Answer 4

PRO-B Cells

Question 5

Intracellular proteins found at this stage are terminal deoxyribonucleotidetransferase (TdT) and recombination-activating genes RAG-1 and RAG-2, which code for enzymes involved in gene rearrangement

Answer 5

PRO-B Cells

Question 6

C-Kit on the pro-B cell interacts with a cell surface molecule called ______ which is found on stromal cells.

Answer 6

stem cell factor

Question 7

Rearrangement of genes on_______ which code for the heavy-chain part of the antibody molecule

Answer 7

chromosome 14

Question 8

Precursor cells

Answer 8

Pre-B CELLS

Question 9

When synthesis of the heavy chain part of the antibody molecule occurs, the_____ stage begins.

Answer 9

pre-B stage

Question 10

The first heavy chains synthesized are the

Answer 10

μ chains

Question 11

The μ chains belong to the class of
immunoglobulins called

Answer 11

IgM

Question 12

These μ chains accumulate in the

Answer 12

cytoplasm

Question 13

Pre-B cells may also express μ chains on the cell surface, accompanied by an unusual light chain molecule called a

Answer 13

SURROGATE LIGHT CHAIN.

Question 14

In immature B cells, the rearrangement of the genetic sequence coding for ______ on

Answer 14

light chains on either chromosome 2 or 22

Question 15

Other surface proteins that appear on the immature B cell include

Answer 15

CD21, CD 40, and major histocompatibility complex (MHC) class II molecules

Question 16

acts as a receptor for a breakdown product of the complement component C3, known as C3d

Answer 16

CD 21

Question 17

are important for interaction of B cells with T cells.

Answer 17

CD40 and MHC class II

Question 18

In addition to IgM, all mature B cells exhibit_______ , another class of antibody molecule, on their surface.

Answer 18

IgD

Question 19

Antigen-dependent activation of B cells takes place in the

Answer 19

follicles of peripheral lymphoid tissue.

Question 20

exhibit identifying markers that include CD25, which is found on both activated T and B cells and acts as a receptor for interleukin-2 (IL-2).

Answer 20

Activated B cells

Question 21

are spherical or ellipsoidal cells between 10 and 20 μm in size and are characterized by the presence of abundant cytoplasmic immunoglobulin and little to no surface immunoglobulin

Answer 21

Plasma cells

Question 22

are not normally found in the blood but are located in germinal centers in the peripheral lymphoid organs

Answer 22

Plasma cells