The plasma membranes of some plant cells use transport proteins to move protons out of the cell against their concentration gradient. this is an example

What is the broadest level of classification of life

Why do oceanic plates tend to subduction when colliding with a continental plate

Which of these is an example of land degradation? a. containers designed to store pollutants leak. b. fertilizers provide too many nutrients to crops. c. garbage is buried so the land can be reclaimed later. d. a drought kills all the plants in an area, leaving bare land