Problem:
Question 1: Explain how menopause affects a woman's bone mineral density, particularly related to estrogen levels. What are other risk factors for osteoporosis and how they contribute?
Question 2: Discuss the relationship between calcium and bone density, and how the body regulates calcium levels in both bone and blood - be sure to include the roles of he parathyroid hormone (PTH), calcitonin, and vitamin D.
Provide a brief explanation for your answer.