6. The organic compounds in living things are organized into groups: carbohydrates, lipids, proteins, and nucleic acids. Which two groups of compounds do living things most commonly use as an energy source?
(A carbohydrates and lipids)
B proteins and nucleic acids
C proteins and carbohydrates
D lipids and nucleic acids


7. Which statement is true about the cells in multicell organisms?
(A They usually have certain special functions. )
B They are prokaryotic cells.
C They can all turn into the same kind of cell if needed.
D They are all identical.


8. Which statement about energy is true for all living things?
A Energy comes only from sunlight.
B Plants convert ATP into glucose for energy.
(C Organisms require energy for survival.)
D Energy cannot be transferred from one organism to another.