227 .205 Lecture Notes - Yolk Sac, Chorionic Villi, Umbilical Cord
Document Summary
Umbilical cord connects the fetus to the uterus. Placenta -is the only organ that is expelled out. Is required for nutrient exchange, gas exchange and elimination of waste products. Uterus i) myometrium- muscles for expulsion of fetus. Strongest muscle in the body ii)endometrium- endometrial glands- important for pregnancy. For histotrophs, before proper development of artery, histotroph provide nutrient. Fetus- in the first month, the urinary bladder and urethra not developed. Urachus is the urethra for the first few months. It contains fetal urine and secretion of gut tube(poo). During delayed delivery(dystocia)- fetus inhales the amniotic fluid (which contains the excretion) straight into lungs. fetus wont survive. Allantois- is predominantly fetal urine and fetal waste products. In cattle it is big and in human it is small. Urethra connects 50% to amnion and 50% to allantois. It is a normal, incidental finding in horses. They are not faeces, and are not formed within the amniotic cavity.
