What is needed for active transport to take place?

Answer 1

there is primary and secondary active transport. Primary active transport requires ATP energy and secondary transport uses the power of electrochemical gradient of some atom/molecule; typically, one of "Glut" transporters uses the power of gradient of Na+ ions (which tend to flow to the cell because there is lower concentration of Na+ in the cell than outside the cell) to transport a glucose molecule to the cell.

Answer 2

Active transport is basically the forced movement of molecules against its concentration gradient (I will explain this later). Let's assume that you have your inner cell, the lipid bilayer, the active transport protein, and the cell environment (outside of the cell). If both the inside of the cell and the environment have 1000 (just a number) ions of calcium, and the cell wants to pump 500 of the external calcium ions into the cell, then it will require an active transport protein. The protein's name is self-explanatory; it transports atoms/molecules/ions to or from a region in a cell. However, active transport is not like passive transport (facilitated diffusion) as it requires ATP (Adenosine Tri-Phosphate)- the energy source of all cells.

Here is a short explanation of concentration gradient. To make it simple, all atoms/molecules/ions want to be evenly distributed. An analogy would be a high pressure air system moving towards a low pressure air system. Why does high pressure move towards low press? The high pressure system contains a higher concentration of whatever we're dealing with (air in this case). The low pressure system is low on air, so the high pressure system moves towards the low pressure system to even out the numbers (They'll mix first, then evenly disperse so that the pressure is equal throughout the new system). In cells, atoms/molecules/ions tend to distribute themselves evenly so that the pressure inside is equal as the pressure outside. The active transport protein pumps (let's take bone marrow and calcium ions as an example) the external calcium ions into the bone marrow, thus allowing the bone marrow to grow at a quicker rate. The pump requires ATP because the ions do NOT wish to go into the bone marrow cell- they would rather stay outside instead if in a crowded area.

Lol, I just realized that the explanation was far from short =P

You should also take a look at the second law of thermodynamics if you're dealing with entropy.

Answer 3

Transport (carrier) protiens and energy in the form of ATP

Answer 4

Energy in the form of ATP.

Channel

Answer 5

sunlight