The fine structure of the guinea pig visceral yolk sac placenta.
D000818:Animals; D003593:Cytoplasm; D004707:Endoderm; D005260:Female; D006168:Guinea Pigs / Q000033:anatomy & histology*; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D010920:Placenta / Q000166:cytology*; D011247:Pregnancy