Figure 4From: Temporal transcriptome analysis of the chicken embryo yolk sacHistology sections of the YS during the last week of chick embryonic development. A. H&E stained YS sections on days E13 to E21. B. PCNA immunostained YS sections on days E13 to E21. Black arrows: Endodermal epithelial cells. Red arrows: Blood islands.Back to article page