Final answer:
The statement is true; DNA encoding Ig genes undergo rearrangement in B cells through a process known as V(D)J recombination, which allows for the generation of a diverse repertoire of antibodies. The statement is True.
Step-by-step explanation:
The rearrangement of gene segments encoding antibody polypeptides indeed occurs at the level of DNA to produce an enormous diversity of antibody molecules. This process, known as V(D)J recombination, takes place specifically in B cells and T cells and is essential for the generation of a diverse repertoire of immunoglobulins (antibodies) and T cell receptors. In B cells, enzymes such as DNA recombinase facilitate the random excision and rearrangement of V (Variable), D (Diversity), and J (Joining) segments in the immunoglobulin heavy and light chain genes. The constant (C) region remains mostly unchanged. These rearrangements enable each B cell to produce a unique antibody with a specific antigen-binding site. The rearrangement process is unique to lymphocytes and does not occur in other cell types. Consequently, the statement that DNA encoding Ig genes undergo rearrangement in B cells but not in other cell types is true.