Membrane Differences: Similarities Between Active And Passive Transport

Cells have the ability to move across the membrane in 2 ways. One way is active transport, which uses energy, and the other is passive transport, which requires no energy. Though the two are similar, they also have a few differences.

Energy is a word you will hear a lot when talking about active transport mechanisms. Unlike passive transport, active transport expands energy to push a substance against its concentration gradient. It's considered "up hill". Energy, in simple words, is the strength it takes to perform a mental or physical action. Active transport is often used in the form of ATP (Adenosine Tri-Phosphate). ATP is an organic chemical found in the body. In metabolism, cells use a large amount of the energy saved to keep their active transport going.

Active transport can be put into two categories. These categories include primary active transport and secondary active transport. Secondary active transport can also be know as cotransport. Primary active transport uses chemical energy when moving molecules across a membrane gradient. An important factor in primary active transport is the sodium-potassium pump. Secondary active transport does know require a

While active transport requires a lot of energy, passive transport require no energy at all. Passive transport depends on permeability of the membrane and the amount of lipids and protein. Passive transport can be broken into four main parts. The first part is called diffusion. Diffusion is the movement of substances from a higher concentration to a lower concentration. Diffusion occurs until the concentration gradient disappears. The next step is called facilitated diffusion. Facilitated diffusion is the carrying of large molecules through the cell membrane. Though it's a little different, facilitated diffusion has the same rules as regular diffusion. Both go from a high concentration to a low