Question

How do molecules like O2, CO2, and small hydrophobic molecules cross cell membranes?

Answer 1

Answer:   Simple Diffusion Across the Cell (Plasma) Membrane

Explanation:

 pretty much the structure of the lipid bilayer allows small, uncharged substances such as oxygen and carbon dioxide, and hydrophobic molecules such as lipids, to pass through the cell membrane, down their concentration gradient, by simple diffusion.

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