Eukaryotes are larger cells with membrane-bounded organelles. Prokarotes are not that large and do not have a nucleus or any memberane-bound organelles.
Idk the options but it could be genetic variation
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Answer:
The suprachiasmatic nuclei enable the nervous system to respond to daily light/dark alterations through their stimulation of melatonin.
Explanation:
Melatonin is a hormone produced naturally by the body. Its function is to regulate the body's circadian cycle. This hormone is stimulated and begins to act by changing between a light environment and a dark environment. This stimulation interacts with the suprachiasmatic nuclei making the nervous system understand this change and luminosity of the environment and respond to the action of melatonin.