Final answer:
Intermediate cells such as megakaryoblasts and proerythroblasts have been identified in hematopoietic stem cells in the bone marrow. These cells can differentiate into various blood cells, including erythrocytes and different white blood cells. Class II MHC molecules, related to antigen presentation, are found exclusively on professional antigen-presenting cells like macrophages, dendritic cells, and B cells.
Step-by-step explanation:
The student's question appears to be about the identification of intermediate cells in the development of blood cells. Specifically, intermediates have been identified in hematopoietic stem cells, which are a type of cell found in the bone marrow that gives rise to various types of blood cells. These intermediate stages include precursor cells with the suffix -blast, such as megakaryoblasts and proerythroblasts. Megakaryoblasts are precursors to megakaryocytes, which eventually form platelets, whereas proerythroblasts develop into reticulocytes before maturing into erythrocytes (red blood cells).
Multipotent stem cells, such as hematopoietic stem cells, have the capacity to differentiate into a limited number of cell lineages. For instance, they can develop into either red blood cells or various types of white blood cells. Lastly, the maturation process of T lymphocytes from multipotent hematopoietic stem cells involves several steps, including initial differentiation in the bone marrow and final maturation in the thymus, where they become thymocytes.
Regarding antigen-presenting molecules, class II MHC molecules are found only on professional antigen-presenting cells, which include macrophages, dendritic cells, and B cells. These cells play a critical role in the immune response by presenting antigens to T cells.