Much of this movement is to regulate the contents of the cell. This includes bringing material into the cell from the extracellular environment or the plasma membrane (endocytosis) or releasing material made within the the cell to the outside (exocytosis).
It really is an easy project...it just takes a little time. All and all, it took me about 6-8 total hours to make 4 bouquets, 10 bouts (my mom made those though) and about 15 centerpieces. I made two bouquets the day before our wedding and the other two the day of the wedding.
Aim to order your invitations about four to five months out so they're ready to mail six to eight weeks before the wedding. If you're having a destination wedding or marrying over the holidays, send out your invites even earlier (10 to 12 weeks before the wedding).