epifiz
The epifiz, or pineal gland, is a small endocrine gland located deep in the brain. In humans it is roughly pea-sized, situated near the center between the two hemispheres in the epithalamus, just above the third ventricle and behind the habenular nuclei. It forms part of the epithalamus and is in close anatomical relationship with nearby structures such as the habenula and the pineal recess of the third ventricle.
Anatomy and histology: The gland consists mainly of pinealocytes and supporting glial cells, with a rich network
Function: The primary role of the pineal gland is the production of melatonin, a hormone synthesized from
Clinical notes: Calcified concretions called corpora arenacea or brain sand are common and tend to increase
Evolution and notes: In many non-mammalian vertebrates, the pineal organ can be photosensitive, functioning as a