Explain how placental villi enable exchange while maternal and fetal blood remain separate, and how the placenta transfers gases, nutrients, wastes, antibodies and hormones.
Explain how the structure and functions of the placenta maintain pregnancy.
a. transport facilitated by proximity of mother and embryo blood vessel;
b. chorionic villi increase surface area for exchange;
c. oxygen and food reach embryo;
d. carbon dioxide and waste matter carried from embryo to mother;
e. immune system of mother protects embryo;
f. barrier function as bloods do not mix;
g. endocrine function as it secretes hormones;
h. human chorionic gonadotropin/HCG prevents degeneration of corpus luteum;
i. production of estrogen maintains endometrium;
j. estrogen increases mammary gland growth;
k. progesterone maintains endometrium;
l. progesterone prevents uterine contractions;