Photoexcitation<span> is the photoelectrochemical process of electron excitation by photon absorption, when the energy of the photon is too low to cause photoionization. The absorption of the photon takes place in accordance with Planck's quantum theory.</span>
Insulin is released into the blood when oxygen levels are low and blood glucose levels are high
DNA, nucleosome, coils, supercoils, chromosome.
Here is what I found, its quite interesting, I hope it helps..
https://www.fbi.gov/services/laboratory/biometric-analysis/codis/codis-and-ndis-fact-sheet