Ciliates are the simplest organisms that live in stagnant water. Their body is completely or partially covered with so-called flagella - short outgrowths that resemble eyelashes. It is thanks to these cilia that the ciliate moves quite dexterously and quickly in the water. One of the most famous species of these protozoa is the slipper ciliate.
Infusoria-shoe - who is it?
This is a fairly common type of protozoan living in fresh water bodies with stagnant water. The main condition for the habitation of ciliates is precisely stagnant reservoirs with a sufficient amount of organic materials in them that serve as food for these protozoa. The second name of this creature is Tailed Paramecia from the genus Paramecium. It is curious that the structure of the ciliate-shoe is the most complex of all representatives of this group of organisms.
Infusoria-shoe. Structure
This single-celled organism got its name from its resemblance to the sole of a shoe. It is curious that such an unusual shape of this creature is due to the dense outer layer of cytoplasm. The entire body of the ciliate-shoe is covered with the smallest cilia (flagella) located in longitudinal rows. It is they who help the ciliates move in the aquatic environment: in 1 second, the simplest can cover a distance 15 times more than itself. The ciliate-shoe moves with the blunt end forward, constantly rotating while moving around its own axis.
Trichocysts are located between the flagella in ciliates - small spindle-shaped organelles that provide it with protection from external stimuli. Each such trichocyst consists of a small body and a tip, which reacts with a sharp shot to any stimulus (heating, collision, cooling). The mouth of this simplest organism has a funnel-shaped form: when food enters it, it is surrounded by a food vacuole, making a small "journey" with it until it is digested. Waste is thrown out through the so-called powder (specific organelle).
The bulk of these creatures is endoplasm (the liquid part of the cytoplasm). Ectoplasm is located next to the cytoplasmic membrane, having a denser consistency and forming a pellicle. Infusoria-slipper absorbs oxygen by its entire surface, existing even at its low concentration in water. All this makes it possible to rightfully call ciliates-slippers the most highly organized protozoa, the pinnacle of their evolution.
Infusoria-shoe. Reproduction
This single-celled organism reproduces in two ways: asexual and sexual. Asexual reproduction occurs due to the transverse division of the cell into two equal parts. At the same time, the body of the ciliate retains its activity. Further, complex processes of regeneration take place, as a result of which each of the parts of the body "completes" all the necessary organelles.
The sexual reproduction method of ciliates-shoes, for obvious reasons, looks somewhat different. Two individuals temporarily "stick together" with each other, forming a kind of bridge between them from the cytoplasm. At this time, the macronuclei of both organisms are destroyed, and the smallest nucleoli begin to divide by meiosis.
After a while, four nuclei appear, three of which are sure to die. The remaining nucleus is divided by mitosis. As a result, two protonuclei are formed - a male and a female. Both individuals begin to exchange "male" protonuclei, after which an additional fusion of two nuclei occurs in each of them, accompanied by the formation of a syncariaon. As a result of the next mitosis, one of the newly formed nuclei becomes a micronucleus, and the second becomes a macronucleus.
