Question

Adam is asked to prove that a particular molecule enters the cell via active transport. which of the following statements can he use as evidence? the molecule was lipid soluble. atp was used for the transport. the molecule moved from a higher to lower concentration.

Answer 1

Answer: ATP was used for the transport.

First answer is just wrong.
And the third answer is used for passive transport because if you go from an area of high to low then you do NOT need ATP. (ATP is an energy source, by the way.)

So think of it this way. In order to ride your bike up a hill you need to use energy (use ATP) as you are riding up that hill you are using ACTIVE transport which mean you need to use your energy to constantly climb up that hill. However, once you make it to the top and ride your bike down the hill you do not need to use energy (passive transport) because the slope/gradient allows you to ride down without having to use any energy. :)

I hope I help explain that haha :) good luck and let me know if you need anymore help! :)