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 is one of the solar system's gas giants, meaning that it is composed entirely of gas. Its upper atmosphere, or surface is composed of three gases. Even though humans will never be able to physically set foot on the planet, satellite visits have revealed a lot about its composition and weather patterns.