When testing a hypothesis, scientists use repeated trials and replication to make sure that they get the same answer each time, and that it isn't just a lucky guess the first time. They need be sure that the answer to their hypothesis is 100% the same every time.
I would say the answer is transport work!
Substances can go through the cell membrane through active and passive transport! Active transport is powered by adenosine triphosphate, ATP!
Answer:
Fe
Explanation:
Iron is a chemical element with symbol Fe and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, right in front of oxygen, forming much of Earth's outer and inner core