Lipids are group of molecules that are insoluble in water and made up of long chain hydrocarbons. Also, lipids are non-polar compounds that cannot be dissolved in polar solvent such as water and they include steroids, waxes, fats and phospholipids. Furthermore, lipids act as structural components of cell membrane.
The energy of the ecosystem can be best described as option C. The amount of energy entering an ecosystem from the Sun is equal to the amount used by organisms plus the amount lost as heat.
