Final answer:
The statement is false; granulocytes originate from myeloid stem cells, while agranulocytes such as lymphocytes come from the lymphoid stem cell line.
Step-by-step explanation:
The statement that both granulocytes and agranulocytes arise from the lymphoid stem cell line is false. Granulocytes and agranulocytes are both types of leukocytes, also known as white blood cells, with different developmental origins. Granulocytes, which include neutrophils, eosinophils, and basophils, are characterized by the presence of granules in their cytoplasm and arise from the myeloid stem cell line. In contrast, agranulocytes, which include monocytes (that mature into macrophages) and lymphocytes (such as B cells, T cells, and natural killer cells), have few to no granules in their cytoplasm. While it is true that monocytes derive from the myeloid lineage, lymphocytes arise from the lymphoid stem cell line and are involved in the adaptive immune system.