-- Question: What does estrogen do?
Answer: Estrogen switches on target sites around a woman's body. It makes bones strong; it lowers cholesterol; it causes the uterus to enlarge during the reproductive cycle. It's really this essential hormone making a woman a woman. The estrogen receptor binds estrogen and switches on those target sites, just as it will switch on the target site -- a breast cancer -- to be able to make it grow as well.
Previous: What is estrogen?