What are some ways in which the structure of a compound influences its function?

2. The heads are hydrophilic and can then interact with water and other polar or charged substances on either side of the bilayer. The bilayer acts as a barrier that allows cells to maintain internal conditions that are different from external conditions, which is monumentally important for cells to operate properly. 

3. Phospholipids demonstrate the intersection of structure and function in another way, too. We already know that fatty acids can be saturated or unsaturated and that unsaturated fatty acids have bends in their chains. Those bends prevent fatty acids from packing close.

"d.) carbon dioxide and hydrogen sulfide"

oxygen +1 most likely