In our article, we invite you to consider the functions of lysosomes in the cell. In addition, we will pay attention to the purpose of this organoid and its structure.
As it has already become clear, the lysosome is an integral part of every cell. And everything that we see, what we touch, and we ourselves are a constructor, consisting of many tiny particles. The cell is the elementary structural unit of all organisms living on planet Earth. She has a number of qualities that allow her to exist on her own:
- own metabolism;
- reproducibility;
- reproduction (self-reproduction);
- development.
Well, now we propose to move on to the organoid of interest to us, consider its structure and highlight the functions of lysosomes in the cell.
Lysosome
Now we will analyze this organelle in more detail and provide you with a classification. Before we list and consider the functions of lysosomes incell, it is necessary to mention a brief history of the discovery. These small granules were first discovered by the scientist de Duve in a liver cell. This event took place in the 50s of the XX century.
Lysosome is a cavity filled with various hydrolytic enzymes (more than 80 types can be counted). It is surrounded by a membrane, it is important to clarify that it is single. The appearance of these organoids is not the same, in most cases it is a rounded shape, not exceeding 0.8 microns in diameter.
The membrane of lysosomes does not have the same thickness, its permeability changes under the influence of certain conditions. So, labilizers (that is, increasing permeability) are:
- thyroxine;
- progesterone;
- vitamin A;
- ultraviolet rays;
- X-ray radiation;
- oxygen, etc.
Reverse effect:
- prednisolone;
- cortisone etc.
In different cells there is not the same number of lysosomes, most of them are in cells with the function of phagocytosis. Examples are macrophages or leukocytes. Also included are those that are capable of absorption, secretion and excretion. They are:
- epithelial cells;
- gut;
- kidney;
- prostate, etc.
Now briefly about the classification of lysosomes. There are two types: primary and secondary. Primary are called cumulative. Among the secondary ones, one can distinguish:
- phagolysosomes;
- cytolysosomes;
- residual bodies.
Functions
Now we propose to isolate a few functions of lysosomes in the cell. So, here you can include:
- cellular digestion;
- autophagy;
- autolysis;
- dissolution of external structures.
Now we will briefly explain the meaning of these terms. You can read more about cellular digestion and autophagy a little later. Now - about what function lysosomes perform during cell death.
This process is called autolysis. The lysosome membrane can be broken, which leads to the release of the enzymes contained in it. As a rule, they cease to perform their main function, as they are simply deactivated in the cytoplasm of the cell.
Violation of one cell is not a problem, but what happens if all lysosomes violate their structure? Then the death of the cell itself occurs. A striking example of autolysis is the death of the tail in frog tadpoles.
Digestion
We mentioned earlier that lysosomes perform the function of digestion in the cell. We invite you to take a closer look at this process. As already mentioned, lysosomes are divided into two groups, while the digestive vacuole also belongs to the secondary ones. It is she who performs the function of digestion in the cell. It is formed by the fusion of a phagosome and a primary lysosome.
Digestive vacuole has a larger size, reaching up to 1, 2 microns. It contains a very large number of inclusions. Here andsubstances that enter the cell are processed. It often happens that they are digested by hydrolysis to low molecular weight particles. The latter can easily pass through the lysosome membrane. Further, the cell needs them to form new organelles.
Autophagy
And what is the function of lysosomes in the cell? We have already said that among their appointments there is such as autophagy. This process is characterized by the capture of components in the cell and destruction by lysosomes. In total, there are 3 types of autophagy:
- micro;
- macro;
- chaperone.
In the first case, the lysosome captures the debris and digests them for energy or building material. This process can occur during fasting. During macroautophagy, the autophagosome and lysosome join together, resulting in the formation of an autophagolysosome. In the latter, the remains of futofagosomes are digested. The third species can be observed exclusively in mammals during times of stress. With this type of autophagy, targeted transport of proteins into lysosomes occurs.
