RT Book, Section
A1 Mescher, Anthony L.
SR Print(0)
ID 1160662354
T1 Hemopoiesis
T2 Junqueira’s Basic Histology: Text and Atlas, 15e
YR 2018
FD 2018
PB McGraw-Hill Education
PP New York, NY
SN 9781260026177
LK accessmedicine.mhmedical.com/content.aspx?aid=1160662354
RD 2024/04/25
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.