What is the difference between pinocytosis and endocytosis

National Library of Medicine, 01 Jan. Available here. Cooper, Geoffrey M. CC BY 2. Samanthi Udayangani holds a B. Degree in Plant Science, M.

Your email address will not be published. Figure Pinocytosis. Figure Receptor mediated endocytosis. Leave a Reply Cancel reply Your email address will not be published. Pinocytosis vs Receptor Mediated Endocytosis. Pinocytosis the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane.

Receptor mediated endocytosis is a process of transporting molecules inside the cell by recognizing and binding to the cell surface receptors and forming vesicles. Pinocytosis does not select molecules to uptake. It absorbs anything in the extracellular fluid. Receptor mediated endocytosis is very specific. It transports specific molecules which are recognized by the receptors. Pinocytosis is less efficient compared to receptor mediated endocytosis. Receptor mediated endocytosis is more efficient than pinocytosis.

Pinocytosis has a simple way of absorbing substances. Receptor mediated endocytosis is comparatively complex than pinocytosis.

This is inside the cell. This is outside. Outside the cell. And you can see the cellular membrane starts to wrap around this, I guess we can think of this a bacteria, then it fully wraps around and then that membrane that was wrapping around the bacteria pinches off and now the bacteria is inside of the cell, and it's wrapped by this membrane. And this process where you're engulfing these large things, we call this Phagocytosis. So this is phago And the prefix I guess you'd say, phago comes from the Greek for "to eat".

So this is literally about cell eating. And in many cases, this thing that is now in here, you could view this as the cell's food, this compartment that is holding this, in this case bacteria, is gonna transport it maybe to a lysosome, so it can be processed and digested in some way. We would call this big compartment, this membrane-bound compartment, we would call this a food vacuole. Food vacuole. Now this scenario down here is similar but different. Over here I have the cell which is I see part of its membrane and it's in magenta right over here.

We can see The Phospholipid Bilayer. That's why I drew two lines for the membrane. And instead of engulfing a large particle or bacteria, it's just engulfing some fluid.

It's engulfing some fluid, so you see it's starting to wrap around this section of fluid, wraps even more around this section of fluid, and then the membrane that was around it completely pinches off and goes into the cell. And I'm drawing all of these things in two dimension, but this would actually be happening in three dimension.

So this wouldn't just be a circle, this would right over here would be a sphere. Then, the remaining vesicle with solutes fuses with a lysosome whose digestive enzymes degrade its content.

However, pinocytosis has a high demand for energy in the form of ATP when compared to phagocytosis, which is another method of endocytosis. Receptor-mediated endocytosis RME is another method of endocytosis responsible for the uptake of solutes into the cell selectively.

In this method, the receptors involve in selecting the molecules. After recognizing a specific solute like a nutrient or protein, a large protein molecule called clathrin is responsible for the formation of a pit in the inner plasma membrane. Then, this pit buds into a coated vesicle in the cytoplasm.

The main importance of this process is that it only allows a small portion of liquid to enter the cell. Also, due to the involvement of clathrin in the process, this type of endocytosis is also called clathrin-mediated endocytosis. Figure 2: Receptor Mediated Endocytosis. In a general sense, receptor-mediated endocytosis is the main method of endocytosis in most types of cells. Some important types of molecules taken up into the cell by this process are hormone-binding molecules, iron-binding proteins like transferrin, low-density lipoprotein cholesterol carriers, etc.

Pinocytosis refers to the ingestion of liquid into a cell by the budding of small vesicles from the cell membrane while receptor-mediated endocytosis refers to an endocytotic mechanism in which specific molecules are ingested into the cell. Thus, this is the main difference between pinocytosis and receptor mediated endocytosis.