Why are chemical reactions important to cells?

Well, every cell in our body is made out of chemical compounds. The different elements are the building blocks of the universe even (one can argue that subatomic particles would be the building blocks as well, but let's not get into that now). They are also therefore the building blocks of your body. At any given moment, there is an incredible amount of chemical reactions going out in your body, all of which help you function normally :)

The answer is telescope.

Molecules called lipids have long hydrocarbon chains that determine the way they act. they can be fats, oils, or hormones, and even exist in our cell membranes