Uhh her parents I guess? not really a doctor you should talk to because that’s just growing up for women.. all of them get their periods, it’s not abnormal
Answer:
They speed up chemical reactions. Without them you wouldn't be alive. They break down macromolecules, and also lower the amount of energy needed for a chemical reaction to happen.
I'm pretty sure that its the 3rd answer
The answer is bones in mammals
