Answer:
red blood cells are formed in the red bone marrow of bones.
Step-by-step explanation:
stem cells in the red blood bone called hemocytoblasts ( a stem cell for blood-cellular elements specifically )give rise to all the formed elements in blood.. If a hemocytoblast commits to becoming a cell called a proerythroblast, (A Proerythroblast is the earliest of four stages in development of the normoblast.)it will develop into a new red blood cell.