The vacuoles are called the cell’s storage tanks.
They are organelles that can store both water and food and they are critical to maintaining the cell wall strength.
All plants have vacuoles but not all animals have them. When you see a plant that looks strong and healthy it’s because it’s vacuoles are filled with water.
During a drought, plants begin to wilt and look limp and this is because the vacuoles’ water supply is low.
A vacuole’s size is another priority for cell function because as the vacuole size grows so does the cell size.
Vacuoles in plants are larger than those in animals and therefore the number of vacuoles in a plant is less than those in animals.
More Information about Vacuoles
The definition of a vacuole is that it is an enclosed compartment or cavity that is membrane-bound and exists in a cell’s cytoplasm for the storage of water, waste, and nutrients.
We find vacuoles in all plant cells, fungal cells, a few bacteria types, protists, and in some animals. Vacuoles are called “fluid-filled compartments,” however they also have solid particles that are isolated.
In plant cells the fluid substance in vacuoles is called “cell sap.”
How does a vacuole work?
A vacuole membrane works in the same way as an animal cell membrane. The membrane lets proteins and materials to easily pass through.
A lot of the waste from a cell will end up in the “central vacuole” and then it is transported out of the plant in a process that is called “transportation.”
The vacuole has three specific ways to move materials and water in and out of its body:
- Elements such as oxygen and water are made up of small molecules that it passes easily through.
- It uses transport proteins to move materials and the proteins break apart parts of the membrane so that the larger molecules can pass through.
- The vacuole makes the decision as to whether it wants a molecule (or not) and its membrane will pump the molecules either in or out.
Peering inside a Vacuole
Finding a vacuole can be tricky because they don’t have any particular size or shape.
Locating them is easier in healthy plant cells because they can take up to 80% of its volume (around 30% in plants that need water).
A majority of the materials inside a vacuole are waste that are deposited by the cell and water.
During photosynthesis a plant will release oxygen and this is a kind of waste that will be deposited in a vacuole.
Other types of waste that you will find inside a vacuole can include nitrogen, RNA, phosphorous, and a jelly-like substance that it gets from cytoplasm.
The process of moving the materials and substances in and out of the cell is called “exocytosis.”
This process is kind of cool as the vacuole wraps part of its own membrane around the waste and the ships it outside of the cell where it’s transported to the roots or leaves of the plant.
Scientists that study vacuoles need to use a high-powered microscope to see them. They believe that small-sized, membranous vesicles fuse together to create vacuoles.
There is a membrane called a “tonoplast or vacuolar membrane” that separates the vacuole from other cell parts, and the membrane can stretch depending upon the cell needs.
Fun Facts about Vacuoles
- Vacuoles have other jobs in plants besides storing water. They also play a part in seed germination and giving structure instructions to blooms and foliage, and in regulating the internal pH.
- Vacuoles in a single-celled organism such as the amoeba are responsible for digestion of the food that they engulf.
- There are vacuoles that exist in freshwater fish and other organisms that are similar, and these are called “contractile vacuoles.” These vacuole types contract and extend to release the excess water that is brought into the body during feeding.
- The vacuole’s membrane is mainly made up of phospholipids.
- In animal cells the main job of the vacuole is in getting rid of waste.
When dead materials or poisons enter the cell area, it’s the vacuoles that will excrete them for the safety and health of the plant or animal.
Interesting Facts about Biology
- Carbohydrates play an important part in making sure that our cells get the energy that is needed.
- We might be familiar with the terms RNA and DNA, but there’s a special kind of RNA that is responsible for moving amino acids to the ribosome called “tRNA”. The “t” stands for transfer.
- Over time, humans can lose the immunity to certain diseases that they had earlier in life.
- Antibiotics are drugs that have been created to kill bacteria.
- Viruses have two types of reproduction cycles: the lytic cycle and the lysogenic cycle.
- Diseases caused by viruses with a lysogenic cycle show symptoms much more slowly than those that are caused by a lytic cycle.
Vacuole Quiz
Now let's test what you have learned!
