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pineal organ

(PIH-nee-ul OR-gun)
A tiny organ in the cerebrum that produces melatonin. Also called pineal body and pineal gland.
Drawing of the inside of the brain showing ventricles (fluid-filled spaces), choroid plexus, hypothalamus, pineal gland, pituitary gland, optic nerve, brain stem, cerebellum, cerebrum, medulla, pons, and spinal cord.Enlarge this image in new window
Anatomy of the inside of the brain, showing the pineal and pituitary glands, optic nerve, ventricles (with cerebrospinal fluid shown in blue), and other parts of the brain.
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