Why is it important to the plant that phloem moves both up and down?

How is the motion of the particles of water at 80 ⁰c different from the motion of the particles of water when it is 30 ⁰c?

Which identifies the main purpose of biological taxonomy?

Match the pollutants. 1. a chlorofluorocarbon smoke 2. a biodegradable organophosphate insecticide freon 3. particle pollution paint 4. hazardous waste monoxide 5. carbon is completely burned malathion 6. carbon is incompletely burned dioxide