Which geographic feature is responsible for bring humans and dogs to north america?
a. bering sea land bridge
b. indian ocean
c. alaskan islands
d. polar ice cap

Which phrase best describes cellular respiration? a. the process where there is a movement of water across a membrane b. the physical division of the cell's cytoplasm c. the process that cells use to obtain energy from food d. the process where there is a movement of molecules to balance out their distribution