Ok but what is the question
<span>The answer is B. We require trees to breath. We would be stuck in an unfortunate situation without our woods. Trees expel carbon dioxide from the environment and discharge oxygen through a procedure called photosynthesis. Basically all creature life on Earth needs oxygen to inhale and woodlands assume a key part in the complex worldwide oxygen cycle.</span>
Oxygen is a small molecule and it's nonpolar, so it easily passes through a cell membrane. Carbon dioxide, the byproduct of cell respiration, is small enough to readily diffuse out of a cell. Small uncharged lipid molecules can pass through the lipid innards of the membrane.
