Question

How does the sodium potassium pump differ from facilitated diffusion?

Answer 1

Hint: Facilitated diffusion and sodium potassium pump are different types of transport system across the cell membrane. Membrane transport is the movement by which particles are transported across or through the membrane.

Complete answer:
Facilitated diffusion is the transport of molecules or ions across a biological phospholipid bilayer membrane. This is a passive-mediated transport, meaning it does not require ATP hydrolysis in the transport process. This is a spontaneous select process, it allows only selective molecules or ions to diffuse. In facilitated diffusion molecules and ions move down their concentration gradient that is why it is classified as passive transport. Facilitated diffusion occurs by integrated transmembrane proteins. There are two types of integrated transmembrane proteins- carrier proteins (glycoproteins) and channel proteins (lipoproteins).

Sodium potassium pump also known as the Na+/K+-ATPase. It is an integral protein pump which is mainly found in the cell membrane of neurons. Na+/K+ pump is classified as direct active transport. Here the ions move against the concentration gradient and so it requires direct hydrolysis of ATP. In this pump sodium and potassium ions are transported across the cell membrane in a ratio of 3 sodium ions for every 2 potassium ions. The sodium ions move outside the cells while the sodium ions move into the cell. Sodium potassium pump helps to stabilize membrane potential which is necessary for creating a voltage difference across the membrane and transmit electrical impulses by axons of nerve cells.

So the differences between facilitated diffusion and sodium potassium pump are:

Facilitated diffusion	Sodium potassium pump
Passive-mediated transport	Active-mediated transport
Does not require ATP	Require ATP
Requires transmembrane proteins	Requires Na+/K+-ATPase enzyme
Transport ions and molecules	Transports sodium and potassium ions only

Note: The transport of substances across the membrane can happen in two ways,
1)Passive transport - This does not require an energy or ATP and it transports molecules from low concentration to high concentration and it is of four types - Simple diffusion, osmosis, facilitated diffusion and filtration
2)Active transport - It requires cellular energy to transport molecules from low concentration to higher concentration and it is of two types - primary and secondary active transport