What is Passive Molecular Transportation?

Question

I know that Active molecular transportation involves Sodium Potassium and Proton Pumps, but what is passive transportation, and please give me an example.

Answer 1

Passive Transport does not require chemical energy to allow molecules across the membrane.

One method of passive transport is simple diffusion. Diffusion is the movement of molecules across a membrane from areas of high concentration to low concentration or along the concentration gradient. These molecules can pass readily directly through the membrane.

Another method is facilitated diffusion. This method is dependant on structures called transport proteins. These proteins are simply pore like structures that span the width of the membrane. The two types are pores and gated channels. Pores always remain open, but gated channels can open and close in response to stimuli. Also, these pores can only transport molecules down the concentration gradient. Some transport proteins are also substrate specific, meaning that they can only transport a specific type of molecule.

Answer 2

Passive transportation: ions move about following the laws of molecular diffusion, difference of concentration or chemical gradient and difference of electrical charge or electrical gradient. The cell membrane allows certain molecules to pass more easily than others, due to the size of channels and chemical conformation of molecules. Therefore, passive transport takes place across a semipermeable membrane.

Example: Spraying perfume in one end of the room and through the process of diffusion you can smell it on the other side of the room. There are no active pumps involved in this type of transport.

Answer 3

passive has to do with simple diffusion. molecules are transfered because they diffuse naturally and no work is necesary for that to occur.