Lipids may consist of fatty acids alone, or they may contain other molecules as well, and fatty acids are the building blocks of lipids. Given these facts, what of lipids may contain other molecules as well among the following options:
- empty spaces
 - big spaces
 - building blocks
 - small parts
 - solid, liquid, gas
 - Organic compounds
 - layers of fat
 - bioaerosols


 

   building blocks      