Today we’ll talk about what a vacuole is. This is another component of the cell, that is, an organoid. An organoid, or organelle, is the particles that make up the cells, the latter, in turn, are the basis of everything that surrounds us.
In fact, the world is not what it seems at first glance. It’s worth picking up a microscope, and our worldview will change dramatically. The first acquaintance with this device occurs back in high school. Teachers should definitely give a lecture on the rules of using a microscope in order to avoid unpleasant incidents in such an exciting lesson. After a short digression, we will tell you what a vacuole is. This is our main question.
Vacuole
We begin the section with the definition. A vacuole is an organoid (single-membrane). It can be found in eukaryotic cells. Immediately introduce a small explanation: eukaryotes are cells containing the nucleus. The latter is separated from the cytoplasm by a double membrane. The value of the nucleus is great, it contains the DNA of the molecule.
So, a vacuole is an organoid that can perform many different functions (we will talk about them a little later). How are these organelles formed? They originate from provacuoles, and they appear before us in the form of membrane vesicles.
It is important to know that all vacuoles can be divided into two groups:
Sometimes pulsating vacuoles are called contractile. They help remove decay products. What else has such a vacuole function, we will consider a little later.
In plant cells, vacuoles occupy more than half the volume, sometimes they merge into one large organoid, which greatly exceeds the size of ordinary ones.
All vacuoles are limited by a membrane, it is called - tonoplast. Inside we can detect cell sap. The latter consists of the following components:
- water;
- monosaccharides;
- disaccharides;
- tannins;
- carbohydrates;
- nitrates;
- phosphates;
- chlorides;
- organic acids and other substances.
Functions
Now we propose to single out the main functions of the organelles we are considering. The vacuole, the functions of which we will now list, can occupy the cell space from 5 to 90 percent. Its purpose directly depends on where this organelle is located.
As for cell types, there are much more in plant ones, and animals have temporary organoids. We have already said that, depending on the location, the vacuole can perform various functions. But we will single out two main ones:
- the relationship of organelles;
- transport function.
Plant cell
Now we turn to a more detailed study of organelles in a plant cell. Cellular vacuole is its main component. Let's list why:
- vacuole absorbs water;
- removes harmful substances;
- in some cases, vacuoles produce milky juice;
- participate in the process of splitting old organelles;
- store nutrients.
As you can see, the role of these organoids is really great. We mentioned that they are able to break down old organoids, that is, they perform the function of lysosomes. Hence, vacuoles can have the enzymes necessary for the hydrolysis of the following substances:
- proteins;
- fats;
- carbohydrates;
- nucleic acids;
- phytohormones;
- volatile and so on.
They also participate in the process of photosynthesis, which is extremely important not only for the plant, but also for other organisms.
Animal cage
Vacuoles can be found at:
- freshwater protozoa ;
- multicellular invertebrates.
In the first case, we will meet contractile vacuoles, which serve as a regulator. That is, they are able to absorb or release excess water. We can attribute many organisms to the second group, among which:
- sponges;
- coelenterates;
- ciliary worms;
- mollusks.
These organisms form digestive vacuoles, which are capable of intracellular digestion. The latter can also form in higher animals, but only in certain cells (phagocytes).