The USA-NPN website will be temporarily unavailable for scheduled maintenance beginning late Sunday, July 26 through early Monday, July 27 (EDT). Thank you for your patience and understanding.
We are undertaking a major revision of our Nature's Notebook data collection app to make it easier and more fun to track plant and animal seasonal activity!
Active transport uses cellular energy to accomplish the transport of molecules, unlike passive transport (such as osmosis) which does not use cellular energy.