<P> The pineal gland , also known as the conarium or epiphysis cerebri , is a small endocrine gland in the vertebrate brain . The pineal gland produces melatonin , a serotonin derived hormone which modulates sleep patterns in both circadian and seasonal cycles . The shape of the gland resembles a pine cone , hence its name . The pineal gland is located in the epithalamus , near the center of the brain , between the two hemispheres , tucked in a groove where the two halves of the thalamus join . </P>
<P> The pineal gland , also known as the conarium or epiphysis cerebri , is a small endocrine gland in the vertebrate brain . The pineal gland produces melatonin , a serotonin derived hormone which modulates sleep patterns in both circadian and seasonal cycles . The shape of the gland resembles a pine cone , hence its name . The pineal gland is located in the epithalamus , near the center of the brain , between the two hemispheres , tucked in a groove where the two halves of the thalamus join . </P>
the hormone that the pineal gland secretes is
the hormone that the pineal gland secretes is
melatonin
melatonin