Autotrophic organisms are able to independently produce energy for the implementation of all life processes. How do they make these transformations? What conditions are necessary for this? Let's find out.
Autotrophic organisms
In Greek, "auto" means "self" and "trophos" means "food". In other words, autotrophic organisms obtain energy from the chemical processes occurring in their organisms. Unlike heterotrophs, which feed only on ready-made organic substances.
Most representatives of the organic world belong to the second group. Animals, fungi, most bacteria are heterotrophs. Plant organisms independently produce organic substances. Viruses are also a separate kingdom of nature. But of all the signs of living organisms, they are only capable of reproducing their own kind by self-assembly. Moreover, being outside the host organism, viruses are absolutely harmless and show no signs of life.
Plants
To autotrophicorganisms are primarily plant-based. This is their main distinguishing feature. Organic substances, in particular the monosaccharide glucose, they form in the process of photosynthesis. It occurs in plant cells, in specialized organelles called chloroplasts. These are two-membrane plastids containing a green pigment. The conditions for the flow of photosynthesis are also the presence of sunlight, water and carbon dioxide.
The essence of photosynthesis
Carbon dioxide enters green cells through special formations - stomata. They consist of two flaps that open to carry out this process. Through them, gas exchange occurs: carbon dioxide enters the cell, and oxygen, formed during photosynthesis, enters the environment. In addition to this gas, which is one of the necessary conditions for life, plants form glucose. They use it as food for growth and development.
Simultaneously with the process of photosynthesis, plants continuously breathe. How can these two opposite processes occur simultaneously? Everything is simple. The process of respiration is less intensive than photosynthesis. Therefore, plants emit more oxygen than carbon dioxide. However, being in a dark room with a lot of plants for a long time, it will become difficult to breathe. The fact is that the amount of oxygen will decrease, and carbon dioxide, on the contrary, will increase.
Generally photosynthetic organismsare of planetary importance. Thanks to them, life exists on planet Earth. And these are not big words. After all, life without oxygen is impossible.
Bacteria
Bacteria are also autotrophic organisms. And we are not talking about blue-green algae, which contain the green pigment chlorophyll in their cells.
There is a special group of organisms - chemotrophs. They break down complex organic compounds into simple ones that can be absorbed by plants. When chemical bonds are broken, a certain amount of energy is released, which chemotrophs use for their life activity. These include nitrogen-fixing, iron and sulfur bacteria. For example, these organisms oxidize ammonia to nitrites - s alts of nitrous acid, sulfur compounds - to s alts of sulfuric acid, sulfates.
But most often among bacteria there is a variety of heterotrophic organisms - saprotrophs. For food, they use the remains of dead organisms or their metabolic products. These are bacteria of putrefaction and fermentation.
Interesting is the fact that in nature there are no substances that bacteria could not break down.
Autotrophic organisms are not always capable of forming organic substances. After all, very often in nature, the living conditions of organisms change. Then these processes become simply impossible. Autotrophs in the process of evolution have adapted to this in their own way. For example, a unicellular animal Euglena green during an unfavorable period is able to feed on ready-made organic substances. BUTwhen living conditions are normalized, it goes back to photosynthesis. Such organisms are called mixotrophs.
Autotrophic organisms play an important role in nature, providing conditions for the existence of all other kingdoms of wildlife.
