TY - CHAP M1 - Book, Section TI - Hemopoiesis A1 - Mescher, Anthony L. PY - 2018 T2 - Junqueira’s Basic Histology: Text and Atlas, 15e AB - Mature blood cells have a relatively short life span and must be continuously replaced with new cells from precursors developing during hemopoiesis (Gr. haima, blood + poiesis, a making). In the early embryo these blood cells arise in the yolk sac mesoderm. In the second trimester, hemopoiesis (also called hematopoiesis) occurs primarily in the developing liver, with the spleen playing a minor role (Figure 13–1). Skeletal elements begin to ossify and bone marrow develops in their medullary cavities, so in the third-trimester marrow of specific bones becomes the major hemopoietic organ. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/03/29 UR - accessmedicine.mhmedical.com/content.aspx?aid=1160662354 ER -