Let us recall the lessons of biology: plankton is ...

Plankton is a living floating mass. It consists of billions of microscopic organisms. This term came from the Greek language and means "wandering", or "floating downstream".

Water as a habitat

Among the huge variety of terrestrial animal and plant life, it is impossible to find organisms that could spend their entire lives in the air. Even skilful "flyers", for example swallows, can not always be worn under the clouds. After all, in the period of nesting, hatching eggs, the withdrawal of chicks, they are tied to the ground, however, like other birds. Yes, birds are not able to fly forever, they periodically need rest. Exactly the same situation with insects. They spend a relatively short time in the air. All of their most important life processes, such as nutrition, reproduction, development, flow on the ground. Also, the whole world of plants is associated with the earth's surface, from the simplest unicellular ones to the woody ones. Absolutely different relations with the habitat of aquatic organisms (hydrobios). This is due to the fact that the physical properties of water and air are different. Water has a much greater density and heaviness. It turns out that the lifting force of this medium is greater than that of air. Accordingly, aquatic inhabitants are able permanently (or, at least, for a long period of their life) to be in a suspended state in the water column, without contact with the bottom. For such organisms, the support is not the soil, but the water medium itself. That's it to such "floating" living creatures in the water column, and freely floating or planktonic organisms belong. In fact, plankton is a collection of such living beings.

Composition and features of "wandering" organisms

For the most part, very small animals and microscopic algae belong to the plankton - not many of them can be seen with the naked eye. A characteristic feature of the organisms of plankton can be called a relatively weak ability to move independently. Most of them are deprived of any bodies responsible for the movement, and are in the full sense of the word a toy of waves. A plant plankton is in a state of limbo due to its incredible ease. Its weight is close to the weight of water that it displaces. However, animal plankton can contain organisms capable of independent movement. This is explained by the presence of various organs of movement, so that they can swim very briskly. However, this movement is very limited. Microorganisms are not even able to resist the weakest current of water. And all because the power of their movement is negligible.

How are the organs of movement organized?

To begin with, it should be noted that animal plankton is the simplest crustacean, as well as fish, lobsters and other organisms that are in the stage of embryonic development. German scientists carried out studies that showed that these animals "hover" in the water column is not at all passive. The crustaceans produce very active movements at short intervals - they evenly swing with swimming tendrils, like birds flying in the air. The complete inactivity of the above-mentioned antennae will lead to the inevitable lowering of the crustacean to the bottom of the reservoir. The same principle applies to other organs of motion in the animal plankton. For example, a rotary apparatus with which rotifers are armed. In fact, planktonic animals can be compared to an airplane, which is kept in the air due to the propeller's work. With the termination of the rotational movement, they slowly plan and sink to the bottom.

"Buffet"

A very important factor for the survival of animal plankton is the fact that the primary source of food, plant substances that make up the plankton, are scattered in the thickness of the water mass, and not attached to the bottom of the reservoir. Due to this, animals in abundance find their necessary food in the surrounding elements. The reserves of algae are able to ensure their existence - this is quite enough to restore the forces that organisms spend on the independent movement necessary for soaring in the water space. In addition, the plankton (the photos cited above fully disclose this natural phenomenon) is a very dense mass, which in turn serves as a source of nutrition for marine animals and fish. For example, whales are big fans of this high-calorie food and its main consumers.

Conclusion

To summarize, it should be noted that in the modern world the term in question has one more meaning - office "plankton". They are workers of intellectual labor, who have a reduced creative component. They spend their lives in offices and other departments. To office plankton are: accountants, secretaries, managers and others. The origin of the offensive epithet is easy to explain: in fact, all these employees are just small fry. Plankton, in a word.