Why does active transport require energy?

5. If a muscle cell in your leg has an internal (cytoplasm) salt concentration of 0.9%, and the fluid outside the cell is 3.5% salt, will water seek to move INTO, OUT of, or BOTH in and out of the muscle cells?

If the leaves of pine trees on the road in an area of heavy salt use start to turn brown, a likely cause could be what?

7. You go to the hospital because you are dehydrated and your cells have shrunk due to water loss. The doctors give you an IV containing a balanced salt solution that mimics the salts in your blood. What will likely happen to the size of your red blood cells when exposed to the IV fluid?

If solutes are large and/or polar they can't cross a membrane using simple diffusion, but if they get assistance or help from protein channels or carrier proteins, they can cross. When they move from a higher to lower concentration using help, it's called what?

This diagram shows three different ways molecules can move from one side of a cell membrane to the other. Which movement(s) of molecules across the cell membrane is active transport?

Identify which way the water will move and what type of solution is depicted in this image