Every day, a large number of microorganisms are concentrated around us, which we do not notice, because the size of microbes is so small that they can only be seen under a microscope. Despite this, the processes of nutrition, respiration, excretion and reproduction characteristic of living organisms take place in their cells.
The most common types of microorganisms
All microorganisms can be divided into several types, which are grouped according to common features in structure, lifestyle and nutrition:
- Bacteria. These are microorganisms that predominantly have a unicellular body, the size of which does not exceed several tens of microns. All bacteria are divided into three types: spherical, rod-shaped and convoluted.
- Viruses. These microbes do not have a cellular structure, their body dimensions are measured in nanometers, so viruses can only be seen with a powerful microscope. The body of a virus is composed of a protein and a nucleic acid. Bacteriophages are bacteria viruses, microphages are fungal viruses.
- Mushrooms. TheseMicroorganisms do not use the process of photosynthesis to convert inorganic substances into organic substances, so they require ready-made food, which they receive from various substrates. Fungi can colonize plants, animals, humans, causing disease.
- Yeast. The body of these microorganisms most often has a rounded shape, the structure in most cases is unicellular. Yeast divides by budding, can be in the soil, on food, in production waste.
Physiology of microorganisms
Microorganisms, like other living organisms, also need food and respiration. They grow, multiply, excrete decay products and eventually die. Features of the nutrition of microorganisms - this is the specificity of obtaining the necessary substances for growth and reproduction, associated with the structure of the microbe.
The physiological processes of microorganisms have some features:
- microbes can grow in oxygen and anoxic environments;
- most microbes can survive even in the harshest environmental conditions;
- microbes have the ability to quickly adapt to changing conditions.
Respiration and nutrition of microorganisms are vital processes that ensure the growth and development of microbes.
How do they eat?
The method of feeding a particular group of microorganisms depends on their structural features. Microbiology is the study of the life of microbes. Microbial nutrition cantake place in different ways. Some microbes use inorganic matter, water and oxygen to form organic matter for nutrition. Other microbes feed on ready-made organic matter found in the environment.
There are several types of microbial feeding mechanisms:
- Passive diffusion. Nutrients enter the cell due to the difference in the concentration of substances on either side of the cytoplasmic membrane.
- Faced diffusion. This process occurs when the concentration of a substance outside the cell is higher than the concentration of a substance inside it. The transfer of substances is carried out by special proteins that bind the molecule of the substance and transfer it to the cytoplasm.
- Active transfer. It is used at very low concentrations of the substrate in the external environment. It is carried out by all the same proteins, only in this case the transfer process is accompanied by energy consumption.
- Translocation of radicals. This method of transferring substances is accompanied by the splitting of a molecule of a substance into components. The transfer is carried out by permease proteins.
Types of microorganisms by way of nutrition
For active growth and reproduction, microorganisms need constant nutrition. Depending on the type of nutrition of microorganisms, the following classification of groups of microbes can be distinguished:
- Autotrophs. Bacteria of this species produce organic substances from inorganic ones through the use of external resources. Aminoautotrophs use air nitrogen molecules, phototrophs- solar energy. Chemotrophs obtain energy by oxidizing organic matter.
- Heterotrophs. They do not produce organic substances on their own, but take ready-made food from the environment. Aminoheterotrophs consume nitrogen from organic matter. Saprophytes receive organic matter from dead organisms, while parasites adapt to life on living organisms.
- Mixotrophs. These organisms are able to use different ways to obtain organic substances.
Respiration of microorganisms
In the process of respiration, redox reactions occur, as a result of which adenosine triphosphoric acid (ATP) is formed, which accumulates chemical energy. Oxidized substances can be alcohols, glucose, organic acids, fats.
By type of respiration, all microorganisms are divided into two groups:
- Aerobes. Microbes belonging to this group can only exist in the presence of molecular oxygen, which they use in oxidative reactions.
- Anaerobes. They can grow and multiply only in an oxygen-free environment, since the process of ATP formation occurs through substrate phosphorylation.
- Facultative anaerobes. These microorganisms can use both methods of oxidizing complex organic substances, so they can grow and multiply in both oxygen and anoxic environments.
- Microaerophiles. A favorable environment for such microbes is an environment with reduced oxygen pressure.
- Capnophilicmicroorganisms. Actively grow and multiply with an increased content of carbon dioxide in the air.
Favorable conditions for the growth and reproduction of microorganisms
Active growth of microorganisms is possible only if there is a nutrient medium necessary for them. With the constant supply of the necessary substances, the cells will begin to actively divide, microbes will multiply, and increase the number of their colony.
The ambient temperature should not be lower than +6 degrees Celsius, the best conditions are a warm environment (+23 … +27 ° С). Bacteria with an aerobic type of respiration need a constant supply of molecular oxygen, anaerobes, on the contrary, oxygen is contraindicated.
Use of microorganisms
Some colonies of bacteria, fungi and yeast are used to organize sewage treatment plants. Bacteria are able to process runoff waste in the course of their life, organizing an environmentally friendly way to get rid of a large amount of production waste.
The purification process is based on the ability of certain types of bacteria to adapt to the composition of the introduced effluents. Those groups of microorganisms for which the nutrient medium is suitable grow and actively multiply. There is an active splitting of complex substances into simpler ones.
Man is a food source for microorganisms
Not all microorganisms benefit humanity. Many of themadapt to life in the human body, exerting a parasitic effect, causing serious diseases.
Parasites are organisms that live inside or on the surface of another living organism and feed on it. Parasites that enter the human body cause significant damage to his he alth. In some cases, death occurs.
Some bacteria, getting into the digestive system, can disrupt the normal microflora of the gastrointestinal tract and lead to a complete breakdown of the mechanism of processing and breakdown of nutrients. Viruses are causative agents of diseases that a person tolerates very hard. Mushrooms are parasites that can place their colonies on the skin, nail plates, causing tissue destruction.
It will be easier for parasitic microorganisms to organize their life activity in the body of a weakened person, whose immunity is not able to fight pathogenic microflora.
In conclusion
In order to know how to use microorganisms or how to deal with them, you need to understand the principle of their physiological processes. If you create all the conditions for the emergence of a suitable environment for them, then the microbes will actively feed and multiply. Germs can be killed, but the process takes quite a long time.
