chpt 2 lesson 3.txt

carbohydrates, lipids, nucleic acids, and proteins.

Living things use carbohydrates as their main source of energy. plants and some animals also use carbs for structural purposes.

are used to store energy. some are important parts of biological membranes and waterproof coverings.

store and transmit hereditary or genetic information.

some control the rate of the actions and regulate cell processes. some form bones and muscles and others transport substances into and out of cells and help to fight diseases.