Grave's Disease is an autoimmune disorder that causes antibodies to bind onto thyroid-stimulating hormone (TSH) receptors on the thyroid. This causes the thyroid to constantly release T3 and T4. What effect would this have on TSH levels?

The body attempts to closely regulate the free hormone concentration in the blood through a variety of factors, including binding of free hormones in the blood by albumin. This causes inhibition of additional hormone release and increased degradation of existing hormone when levels are too high. For example, triiodothyronine (T3) is able to prevent additional release of T3 from the thyroid when its levels are too high.

What kind of feedback mechanism does T3 employ?

Which of the following are examples of positive feedback mechanisms in the body?

I. Fever during illness

II. Loss of bone mass in osteoporosis

III. Contraction during childbirth

The body attempts to closely regulate the free hormone concentration in the blood through a variety of factors, including binding of free hormones in the blood by albumin. This causes inhibition of additional hormone release and increased degradation of existing hormone when levels are too high. There are times, however, when the body needs to continue having high levels of certain hormones. For example, oxytocin, a hormone released during childbirth, stimulates the uterus to contract. Existing levels of oxytocin in the blood encourage additional oxytocin release.

What kind of feedback mechanism does oxytocin employ?

Insulin is a peptide hormone responsible for lowering blood glucose levels. In some forms of diabetes mellitus, insulin is lacking. Why do diabetics inject insulin into their bodies rather than consuming an insulin pill?

Which hormones act as antagonists to bone growth?