Thymocytes are derived from ( ). A: bone marrow B: thymus C: lymph node D: spleen

Immature thymocytes (DN developing T cells) share what surface proteins with germ cells <br/>and neural crest cells? A: the C-Kit receptor B: class II MHC molecules C: B7 D: the cytoplasmic signaling peptides (ζ, ε, etc.) of the CD3 E: CD8 and CD4

In the thymus, thymic stromal cells(TSCs) are interconnected into a network structure. These cells carry a large number of surface molecules and can secrete a variety of thymic hormones and cytokines, which provides a suitable microenvironment for the development and maturation of thymocytes. The types of TSCs include ( ). A: epithelial cell B: macrophage C: dendritic cell D: neutrophil