Illustration: Todd Detwiler
1. Pineal Gland
Named for its pinecone shape, the pineal gland is tucked between the two hemispheres of the brain. It's still a bit of a mystery, though we know it produces the sleep hormone, melatonin.
2. Pituitary Gland
Known as the master gland, this pea-size organ releases hormones that stimulate the other glands to, in turn, release their hormones.
3. Thyroid Gland
Think of this gland as the thermostat for your metabolism: It can increase or decrease the rate of calorie burn by releasing more or less thyroid hormone.
4. Adrenal Glands
Perched atop your kidneys, these glands secrete hormones that control your "fight or flight" response to stress (cortisol and adrenaline) and your blood pressure (aldosterone), among others.
These organs produce more than eggs; they manufacture and release the most important hormones for female development: estrogen, progesterone, and—yes—testosterone.
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