What is structure 2, and how does it help sustain life?
A.
Structure 2 is a chloroplast, which is the site of photosynthesis.
B.
Structure 2 is the nucleus, which serves as the control center of the cell.
C.
Structure 2 is the cell membrane, which controls what enters and leaves the cell.
D.
Structure 2 is the cytoplasm, which contains organelles and is the site of many cell processes.