Difference Between Endocytosis and Phagocytosis

The key difference between endocytosis and phagocytosis is that endocytosis is the process of taking the matter into the cell by forming cell membrane vesicles while phagocytosis is the process of taking the large solid matter into the cell by forming phagosomes.

Endocytosis and phagocytosis are two transport mechanisms that take materials into the cell. Endocytosis is of three categories. Among them, phagocytosis and pinocytosis are the two most common types. Moreover, phagocytosis is a form of endocytosis. During both mechanisms, materials are taken in inside vesicles. These materials include cell debris, enzymes, dead cells, pathogens, hormones, nutrients, etc. The opposite mechanism of endocytosis is exocytosis, which involves the removal of material from the cell enclosed in vesicles.

CONTENTS

1. Overview and Key Difference
2. What is Endocytosis
3. What is Phagocytosis
4. Similarities Between Endocytosis and Phagocytosis
5. Side by Side Comparison – Endocytosis vs Phagocytosis in Tabular Form
6. Summary

What is Endocytosis?

Endocytosis is the process of taking materials and fluid into the cell by enclosing them in vesicles. The enclosure of material takes place by an area of the plasma membrane that pinches off into the cell by forming a vesicle.  The three forms of endocytosis are phagocytosis, pinocytosis and receptor-mediated endocytosis. Thus, phagocytosis involves uptake of material such as large solid materials while pinocytosis is based on the uptake of fluids along with its solutes.

Moreover, the vesicle formed during phagocytosis is called the phagosome, and in pinocytosis, it is referred to as the pinosome. Generally, the pinosome is formed by Clathrin-coated pits in the plasma membrane. But some of the pinocytic pathways lack clathrin-coated vesicles. The phagosome is comparatively larger than the pinosome since phagosome involves larger solid material. Pinocytosis is a common process in almost all the cells of the body.

What is Phagocytosis?

Phagocytosis is a process of taking the large solid matter into the cell by forming phagosomes. Therefore, it is a form of endocytosis. The materials taken into the cell under this mechanism includes cell debris, pathogens such as bacteria, dead cells, dust particles, small mineral particles, etc. Moreover, most of the immune cells such as tissue macrophages, neutrophils and monocytes are professional phagocytoses performing cells.

The other types of phagocytic cells are present in Kupffer cells in the liver, the pigmented epithelium of the eye, Langerhans cells in the skin and the microglia in the brain. Generally, phagocytosis is a defence mechanism. Hence, it is involved in destroying the invading pathogens by engulfing them into phagosomes and later destroying inside the cell. A lytic action takes place inside the cell where a lysosome binds to the phagosome and release lytic enzymes to destroy the engulfed pathogen/ solid matter. ANd, this structure is called a phagolysosome.

What are the Similarities Between Endocytosis and Phagocytosis?

• Both endocytosis and phagocytosis are two mechanisms involved in taking materials into the cell.
• Both mechanisms form vesicles for transportation.

What is the Difference Between Endocytosis and Phagocytosis?

The uptake of materials from the extracellular environment into the cell occurs via two mechanisms; endocytosis and phagocytosis. Endocytosis, basically, involves in taking up fluid or suspended particles into the cell. Phagocytosis involves taking up the particulate matter to the cell. This is the key difference between endocytosis and phagocytosis. However, phagocytosis is a type of endocytosis.

Below infographic presents the difference between endocytosis and phagocytosis comparatively.

Summary – Endocytosis vs Phagocytosis

Both endocytosis and phagocytosis are two mechanisms that involve in taking material into the cell. The key difference between endocytosis and phagocytosis is that endocytosis is the process of taking in matter and fluid into the cell by forming cell membrane vesicles while phagocytosis is the process of taking the large solid matter into the cell by forming phagosomes. The two main forms of endocytosis are phagocytosis and pinocytosis. Phagocytosis involves uptake of material such as large solid materials while pinocytosis is based on the uptake of fluids along with its solutes. Generally, phagocytosis is a defence mechanism. Hence it is used to destroy invading pathogens by engulfing them into phagosomes and later destroying inside the cell. This summarizes the difference between endocytosis and phagocytosis.

Reference:

1. Britannica, The Editors of Encyclopaedia. “Phagocytosis.” Encyclopædia Britannica, Encyclopædia Britannica, Inc., 3 Jan. 2018. Available here  
2.“Endocytosis.” Elements and Atoms. Available here 

Image Courtesy:

1.”0309 Three Forms of Endocytosis”By OpenStax  (CC BY 4.0) via Commons Wikimedia  
2.”Phagocytosis2″By GrahamColm at English Wikipedia, (CC BY-SA 3.0) via Commons Wikimedia