Cell division is the process by which a parent cell divides into two or more daughter cells. Cell division usually occurs as part of a larger cell cycle.
Neptune's atmosphere, like Jupiter's and Saturn's, is composed primarily of hydrogen and helium, along with traces of hydrocarbons and possibly nitrogen; it contains a higher proportion of ices such as water, ammonia, and methane.
Neptune's atmosphere is made from about 80% hydrogen and 19% helium. It also contains a small amount water and methane, which give rise to the green-bluish color. The dark blue and bright white features of the atmosphere help distinguish Neptune from Uranus. The thin cirrus-like white clouds contain methane ice. When hydrocarbon snowflakes form in Neptune's atmosphere they melt before reaching the surface because of the high pressure.