1. Children in puberty are in a state of positive nitrogen balance, in which nitrogen intake exceeds excretion. This results from the fact that they are growing rapidly and incorporating nitrogen as protein into new tissue.

2. Labor is stimulated by prostaglandins. Aspirin and ibuprofen inhibit cyclooxygenase and thus inhibit prostaglandin synthesis.

3. A loss of the connection between the hypothalamus and anterior pituitary should not affect her milk production, but will affect her future ovarian cycles. Fundamentally, this is because lactation is controlled by the presence or absence of prolactin inhibiting hormone (PIH) from the hypothalamus, whereas the ovarian cycles are regulated by gonadotropin releasing hormone (GnRH). That is, lactation occurs if PIH is absent, and severing the portal blood vessels ensures that PIH will be absent. Oxytocin, required for milk let-down, comes from the posterior pituitary and does not depend on the portal system. Ovarian cycling, however, requires that GnRH get from the hypothalamus to the anterior pituitary, and severance of the portal vessels prevents that.

4. In the first 6 weeks of pregnancy, the corpus luteum is the major source of progesterone, which is needed to maintain the pregnancy. Therefore, if the ovaries are removed (or even if just the corpus luteum is removed), the pregnancy is aborted. After 6 weeks, the placenta produces the necessary progesterone, the corpus luteum has degenerated, and the ovaries are dormant. Removing them would not change the course of the pregnancy.

5. Hearing the cry of an infant can lead to stimulation of the hypothalamus, which in turn can cause the posterior pituitary to release oxytocin and the mammary glands to release milk.

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