Active and passive transport of solutes across a membrane typically differ in which of the following ways?

Question

anonymous · Answer

a)Active transport is usually against the concentration gradient of the solute, whereas passive transport is always down the concentration gradient of the solute. 

-Active transport is is going from Low Concentration to High Concentration




b)Active transport always involves the utilization of cellular energy, whereas passive transport does not require cellular energy. 

- Active transport requires energy, passive trasport does not




c)Active transport always requires the use of transport proteins, but passive transport can sometimes be accomplished without a protein. 

- Active transport requires a Carrier Protein. 

Facillitated Diffusion- (Which is passive) Uses a carrier or a Channel protein

Diffusion- (which is passive) Does not need a protein.

anonymous · Answer

i know this question so i know there options

frostbite · Answer

Yea well.... nothing more to say beside i am going to expand it abit with a few equations:
Thermodynamically, the movement:
$$\Delta G = G(after-transport) - G(before-transport)$$
If ΔG<0 the transportation is spontaneous (passive). If ΔG>0 then the transport of the molecules have to be linked to a energy-supplying reaction, which could be the hydrolyzation of ATP to ADP and Pi, that have a ΔG<0 (ΔG≈-31 KJ/mol). This kind of transport we call active transport. (note: it is important to remember that the full change in the systems free energy (ΔG(transported molecule)+ΔG(ATP)) is always negative. Also if the molecules that are seposed to be transported are changed another equation is applyed for this.

mayankdevnani · Answer

http://answers.yahoo.com/question/index?qid=20081002135403AANEFw8

jadedry · Answer

Passive transport occurs when there is an imbalance in the amount of a certain material on two sides. (example- glucose in semipermeable tubing immersed in distilled water). Passive transport is the act of the material in question spreading to the side with less of the material so that there is an equal amount of it on both sides. Think of a concentration gradient. 

Active transport goes against a concentration gradient since it is actively being pulled across , it is not just relying on the concentration gradient.