The structure of DNA resembles a twisted ladder. Which structural components form the rungs of the ladder? A deoxyribose sugars
B phosphate groups
C nitrogenous base pairs
D ribosomes
answer is nitrogenous base pairs

Label the following as inner or outer planets; a) has 67 moons made mostly of hydrogen and helium b) has rings c)no moons, high volcanic activity d) known as the red planet, has 2 moons e) very thin atmosphere, moons or rings

True or false 5. carrier proteins have the ability to to change shape and physicially move molecules across the cell membrane. 6. in a facilitated diffusion, the concentration of the molecules to be moved across the cell membrane is higher inside the the cell.

When muscles contract, they become .