The ozone layer in the stratosphere protects earth from the sun's ultraviolet radiation. where does the ozone come from?

Ozone is created when energetic photons from the sun such as the UV strikes a molecule of oxygen splitting the two atoms. The radical atom then bombards with another oxygen molecule and join to create an O3 complex called ozone. The rate at which the ozone is created is balanced by the rate at which it is destroyed by the same energetic photons.

allowed for the prediction of the properties of missing elements.

the principle of segregation describes how pairs of gene variants are separated into reproductive cells. from his data, mendel formulated the principle of segregation. we now know that the segregation of genes occurs during meiosis in eukaryotes, which is a process that produces reproductive cells called gametes.