Answer:
Ozone
Explanation:
In the stratosphere, ozone is created primarily by ultraviolet radiation. When high-energy ultraviolet rays strike ordinary oxygen molecules (O2), they split the molecule into two single oxygen atoms, known as atomic oxygen.
Evaporation of water from the oceans.
Human stem cells haven’t specialized in to create an organ. This means that they can be manipulated to create a variety of organs for organ transplant and therefore lowers the risk of rejection
