The key difference between vacuoles and vesicles is that the vacuoles are large membrane-bound sacs used as storage while the vesicles are small membrane-bound sacs used as storage and to transport inside the eukaryotic cells.
A cell is like a bag of chemicals, which is capable of survival and self-replication. The cell membrane separates the cell interior from the external environment in animal cells. Therefore, in plants cells, the cell wall is the outer boundary that separates the cell interior from the external environment. Generally, a cell contains various types of organelles in its cytoplasm. These organelles include the nucleus, Golgi apparatus, mitochondria, endoplasmic reticulum, ribosomes, centrioles, vesicles, etc.
CONTENTS
1. Overview and Key Difference
2. What are Vacuoles
3. What are Vesicles
4. Similarities Between Vacuoles and Vesicles
5. Side by Side Comparison – Vacuoles vs Vesicles in Tabular Form
6. Summary
What are Vacuoles?
A vacuole appears like a thin membrane-bound sac, and it is a fluid-filled sac. Vacuoles found in animal cells are relatively small vacuoles. Common vacuoles present in animal cells are phagocytic vacuoles, food vacuoles, contractile vacuoles, etc. In plant cells, the vacuoles found are very large. Furthermore, several small vacuoles are present inside an animal cell while one big vacuole is present inside the plant cell more often. The vacuole is very significant in parenchyma cells. Tonoplast is the membrane that encloses a vacuole. Cell sap is the fluid found inside the vacuole. It contains mineral salts, sugars, organic acids, oxygen, carbon dioxide, pigments, waste and certain secondary metabolites.
Water enters the vacuole by osmosis through the partially permeable tonoplast. When water enters the vacuole, a pressure develops inside the vacuole. Due to this pressure, cytoplasm is pushed towards the cell wall. This is important in cell growth as well as in normal water relations of the plant. The pigments that are found inside the vacuoles are responsible for the color of flowers, fruits, buds and leaves. The colors of these structures are important to attract animals for seed dispersal and pollination. Sometimes plant vacuoles contain hydrolytic enzymes.
Figure 01: Vacuole
Moreover, when the cell becomes aged, the tonoplast loses its partial permeability, and the hydrolytic enzymes escape to the cytoplasm causing autolysis. Waste products and certain secondary metabolites also accumulate in the vacuoles with time. In addition, vacuoles also contain food reserves such as sugars and mineral salts that the cytoplasm use when required.
What are Vesicles?
Vesicle is also a sac that surrounds by a thin membrane. Those vesicles are used to store materials that can be naturally prepared or artificially prepared liposomes. Most vesicles have a specialized function to perform. Vesicles that are separated from the cytoplasm by one phospholipid bilayer are called unilamellar vesicles. The vesicles separated from the cytoplasm by more than one phospholipid bilayer are called multilamellar vesicles.
Figure 02: Vesicles
Likewise, vesicles can perform different functions such as storage, transport and digestion of waste products, etc. The membrane enclosing the vesicle is similar in nature to the plasma membrane. Therefore, the membrane of the vesicle can fuse with the plasma membrane, which allows the vesicle to release its products to the exterior of the cell. Since the vesicles separate from the cytoplasm, sometimes, it is possible to maintain different conditions inside the vesicles. Vesicles are sometimes used as chambers of chemical reactions. There are different types of vesicles such as vacuoles, lysosomes, transport vesicles, secretory vesicles and other types of vesicles.
What are the Similarities Between Vacuoles and Vesicles?
- Both vacuoles and vesicles are sac-like structures present inside the cells.
- In fact, vacuoles are a type of vesicles.
- Also, a thin membrane surrounds both of them.
- Furthermore, fluid fill them both.
- Moreover, both are visible under the microscope.
- Both are useful to store in eukaryotic cells.
What is the Difference Between Vacuoles and Vesicles?
Vacuoles are large membrane-bound sacs that mostly contain water. On the other hand, vesicles are small membrane-bound sacs that contain water, nutrients, enzymes, wastes, etc. This is the key difference between vacuoles and vesicles. Furthermore, one cell normally contains one or several vacuoles. But, a number of vesicles in a cell is higher than the number of vacuoles. Hence, it is also a difference between vacuoles and vesicles.
Moreover, a further difference between vacuoles and vesicles is that the vacuoles are mainly for water storage while vesicles are for storage as well as transport.
The below infographic on the difference between vacuoles and vesicles shows the differences comparatively.
Summary – Vacuoles vs Vesicles
Vacuoles are a type of vesicles that are present in cells. Generally, vacuoles are large membrane-bound sacs that store water. Animal cells have several small vacuoles while plant cells have a large vacuole at the middle of the cell. Vesicles are normally small membrane-bound sacs that store and transport things. Vesicles contain water, nutrients, enzymes, wastes and harmful compounds. This summarizes the difference between vacuoles and vesicles.
Reference:
1. “Vesicle (Biology and Chemistry).” Wikipedia, Wikimedia Foundation, 17 Jan. 2019. Available here
2. Wada, Y. “Vacuoles in Mammals: a Subcellular Structure Indispensable for Early Embryogenesis.”Current Neurology and Neuroscience Reports., U.S. National Library of Medicine. Available here
Image Courtesy:
1.”13578808733″ by Siyavula Education (CC BY 2.0) via Flickr
2.”Plant cell structure-en”By LadyofHats – Own work (Public Domain) via Commons Wikimedia