Somebody plzzz help me ASAP..

There are six elements that make up most of the human body. which of the following is not one of these six elements?

Cells tend to have a relatively small and uniform size. why aren’t cells larger?

In addition to seeds, which of the following characteristics are unique to the seed-producing plants? a) sporopollenin b) lignin present in cell walls c) pollen d) use of air currents as a dispersal agent e) megaphylls