<prompt> Erythopoiesis in gestation age takes place in -Yolk sacPlacentaAmniotic sacChorion  <response>: Ans. is a i.e., Yolk sac Erythropoiesis siteso Intrauterine 0-10 weeks-Yolk sac 10 weeks - 5 months-Liver major organ and spleen 5 month onwrard-Bone marrowo After birth Upto 20 years-Bone marrow of all bones After 20 years-Flat bones of axial skeletal and proximal end of humerus and femur. 