The shape of an enzymes active site fits the shape of a certain molecule that is affected by the enzyme. It's like a puzzle piece fitting into another puzzle piece. The molecule in the reaction being catalyzed fits into the enzyme. Hopefully this helps, this is how I was taught
They would be a community.
I'm thinking it is rain gauge
Increased hunger, sleeping, increased appetite, an increase of bones and muscles, and growing pains.
The order is:
interphase
prophase
metaphase
anaphase
telophase
(the way i remember it is "IPMAT")