What happens during fertilization that makes the offspring unique from the original cells?

The union of an egg and sperm forming a zygote is known in biology as fertilization, during this process the zygote becomes a morula, meaning that the female reproductive cell divides after that union generating many other cells together into a solid ball of cells, giving rise to the embryo with the potential for development, fostered by chemical reactions among the sperm enzymes and the egg's plasma; mitosis and meiosis are included throughout the whole process.

Explanation:

absorption lines are where light has been absorbed by the atom thus you see a dip in the spectrum whereas.

emission spectra have spikes in the spectra due to atoms releasing photons at those wavelengths.

explanation: