ATP synthase is powered or driven by flowing through it, in order to make ATP molecules. A. NADH
B. protons or hydrogen ions
C. protons
D. hydrogen ions
E. hydrogen or NADH

The model illustrates a process by which a substance is taken up by a cell

What's wrong with this ecological pyramid? (multiple choice)1. secondary consumers should be at the bottom of the pyramid2. the sun has an arrow leading to decomposers 3. primary consumers should come after the sun4. energy retained should increase from the bottom to the top5. the sun should be at the bottom of the pyramid

Ivan is looking at a cross section of a stem taken from a vascular plant. he sees two different types of vascular tissue: the xylem, which is closer to the center of the stem, and the phloem, located around the xylem, closer to the outside of the stem. how do these two structures work together in a living plant?