Lipids are organic compounds that contain the same elements as carbohydrates: carbon, hydrogen, and oxygen. However, the hydrogen-to-oxygen ratio is always greater than 2:1. More important for biological systems, the carbon-to-hydrogen bonds are nonpolar covalent, which means that lipids are fat soluble and will not dissolve in water. There are four biologically important lipids:
A. <span>The total amount of matter and energy remained the same, because energy can't be lost, it can only be transferred into a different sourceof energy.
