Which of the following is an example of facilitated diffusion? a. sugar is transported into the cell via an energy-consuming process b. hydrogen ions are pumped out of the cell against their concentration gradient c. carbon dioxide exits the cell, passing directly through the cell membrane d. water moves out of the cell, passing through channel proteins in the cell membrane

D. which is also known as osmosis a form of facilitated diffusion (doesn't require energy)

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands

the answer is c. it will give up it's valence electron to the other atom.