The recently discovered hormones, melatonin and serotonin, are secreted at the ends of nerve fibres by the activity of:

$I.$ Sleep-wake cycle,$II.$ Body temperature,$III.$ Pigmentation,$IV.$ Metabolism,$V.$ Defence capability. All of the above-mentioned activities are influenced/regulated by:

The pineal gland originates from the:

"Pinealocytes" are found in which of the following?

$I.$ Sleep-wake cycle, $II.$ Body temperature, $III.$ Pigmentation, $IV.$ Metabolism, $V.$ Defense capability. All of the above-written activities are influenced/regulated by:

The function of the pineal body is to