Describe cellular structures that allow cells to extract and use energy from food, eliminate wastes, and respond to the environment (e.g., every cell is covered by a membrane that controls what goes into and out of the cell). [Cell structure and function]
Describe how DNA molecules are long chains linking four kinds of smaller molecules, whose sequence encodes genetic information.
Describe how genes (DNA segments) provide instructions for assembling protein molecules in cells. [Protein synthesis]
Describe how proteins control life functions (e.g., the proteins myosin and actin interact to cause muscular contraction; the protein hemoglobin carries oxygen in some organisms). [Function of proteins in cells and organisms]