A living organism is very complex. Even a small cell of our body has its own complex structure, consisting of organelles and inclusions, which, like human organs, perform their functions. In this article we will describe one of the structural units of the cell. This is a centriole.
What is a centriole
In our cell there are specialized and general purpose organelles. The second type is the cell center, consisting of two centrioles and one centrosphere. Why does the cell need all this? For the assembly of microtubules, which, with their strength, provide support to the cytoskeleton and support active intracellular transport.
Thus, the centriole is an organelle of a eukaryotic cell, which has a cylindrical shape and is responsible for the assembly of microtubules. It is a self-regulating structure that doubles at the cell center.
Structure of a centriole
Each centriole is a cylinder, the wall of which consists of nine triplets, or complexes of three microtubules of the same length and diameter.
See the green tubes in the picture? This is the centriole shown in moresimple form, without internal components, with triplets.
Triplets are located to each other at an angle of 50°, the upper end is connected to the adjacent triplet, and the other - to the center of the cylinder. Thus, in the inner part, a star figure and a kind of wheel with spokes are formed.
As we already know, the cell center has two centrioles. Relative to each other, they are perpendicular, that is, one of them (daughter) rests with its end against the side surface of the other (maternal). The first arises by doubling the mother.
The latter can also be distinguished by the specific balls surrounding it. This is an electron-dense rim, consisting of satellites and tightly connected to the outer side of each triplet. What are they for? This is where microtubules are assembled. When this process is completed, they are sent to different parts of the cell to integrate into its cytoskeleton.
Functions of the centriole
So what do we already know? The centriole is the organelle of the cell center. From here you can guess about its functions:
- Microtubules are assembled on it. This is very important for the cell, which, like a person, needs support, and if our skeleton with muscles provides it, then the cell has a cytoskeleton consisting of just these same microtubules.
- She takes part in the formation of the basal bodies of flagella and cilia. And this is the basis of the basics of cell movement in the air and in the aquatic environment. Without it, even fertilizationegg cell motile sperm would be impossible. This would deprive us of such a rich diversity of species forms, and to some extent - the evolution of organisms. The cilia, in turn, help remove dust.
- It plays an important role in the formation of the mitotic spindle, which, shortening, breaks the doubled chromosomes for their subsequent despiralization and the formation of the nuclear substance of a new cell.
It's amazing how everything in the living world is interconnected: cells make up tissues, tissues make up organs, and we are made of them. It turns out that even such a small organoid as a centriole performs vital functions and plays an important role in the formation of a cell and its subsequent proper functioning.