Cells must be able to move molecules, digest particles, and secrete materials in order to survive. For many cellular functions, vesicles are used. In this lesson, we will learn about vesicles and how they are used by cells.
What Are Vesicles?
Cells are the basic building blocks of all living things.
In order for organisms to survive, their cells must be able to complete numerous functions. Many of these functions require the cells to move molecules from one part of the cell to the other. When a cell needs to move a molecule many times, it uses vesicles.Vesicles are cellular organelles that are composed of a lipid bilayer.
You can think of vesicles as cellular envelopes that are used to transport materials from one place to another. Vesicles also function in metabolism and enzyme storage as well. This diagram shows the overall structure of a simple vesicle:
Function and Types of Vesicles
Vesicles play many roles within a cell. Since vesicles are composed of a lipid bilayer, they can have a completely self-contained environment that is different from the inside of the cell.
There are essentially four types of vesicles used by cells. They are vacuoles, lysosomes, transport vesicles, and secretory vesicles.Vacuoles are vesicles that contain mostly water. They are able to regulate the pressure and water level of the cell to control the conditions of the internal environment.
Plant cells are known to have large vacuoles. This diagram depicts the large vacuole inside a plant cell:
|Contain mostly water and regulate the cell’s water pressure||Contain digestive enzymes to get rid of cellular waste and break down food particles||Move molecules within the cell||Contain chemicals to secrete into the cell when needed|
Once you’re finished, you should be able to:
- Recall what vesicles are and their structure and functions
- List the four types of vesicles used by cells and state their purposes