The scientific method has five basic steps, plus one feedback step: Make an observation. Ask a question. Form a hypothesis, or testable explanation.
The way that I know it is that cells make up tissue, tissue makes up organs, and organs make up organ systems.
C.they separate atria from ventricles, and ventricles from the large arteries that leave them.
That will allow materials into via a passive transport Mechanism and as water and solute movement
