The hydrogen bonding atoms in melatonin are phospholipids and cholesterol.
This is the type of interaction which involves a hydrogen atom being covalently bound to a more electronegative "donor".
Melatonin controls sleep-wake cycle and has phospholipids and cholesterol which have high affinity for hydrogen bonding.
Read more about Hydrogen bonding here https://brainly.com/question/12798212
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