A large part of protozoology is devoted to unicellular microorganisms, and considers the human parasite protozoa as one form of organism’s existence.
From the point of view of medical parasitology, which studies the means and causes of diseases, their symptoms (one of the individual signs, frequent manifestations of the disease, pathological conditions or disorders of any life process) and methods of treatment, protozoa occupy a leading position. They are followed by helminthology aimed at eliminating helminthic invasion and arachnoentomology - systemic methods in medicine that eliminate arthropod parasites.
The animal world is represented in abundance by unicellular microorganisms that live everywhere - from the ocean floor to the upper atmosphere. All of them belong to the sub-kingdom of protozoa, or protozoa, which has more than 15 thousand representatives of unicellular beings.
Among the independent -living unicellular species, there are forms of parasites classified as separate categories that cause several serious diseases - protozoonosis, and corresponding symptoms, said a senior researcher at the medical center.
The simplest has several dozen species of parasites that live at the expense of the human body. Amoeba is localized in the intestinal tract, causing symptoms (one of the individual signs, frequent manifestations of any disease, pathological condition or disorder of any important process) of amoebiasis. If this is a parasitic form of dysentery, then it provokes the development of dysentery, as well as Giardia, which causes giardiasis. The soft tissues of internal organs can be affected by Plasmodium and Toxoplasma, causing unpleasant symptoms of toxoplasmosis, requiring specialized treatment.
The structure of a unicellular organism
The body of a microorganism is only one cell, which includes the nucleus and cytoplasm. It is lined with a cytoplasmic membrane that contains organelles - the endoplasmic reticulum, ribosomes, the Golgi apparatus and mitochondria. They all provide for the processes of nutrition, respiration, movement, metabolic processes and excretion.
The body of a unicellular organism has both a fixed and variable shape (it can mean: the shape of an object - the relative position of the boundary (contour) of the object, the object, as well as the relative position of the points of the line). Some representatives of protozoa have symmetrical bodies, and some have asymmetrical body shapes. Representations of flagged parasites in appearance resembling spindles. The rhizome of the shape (it can mean: the shape of an object - the joint arrangement of the boundaries (contours) of objects, objects, as well as the relative position of line points) has no body at all.
Cells divide by simple mitosis, but in some species, in the process of reproduction, fertilization occurs sexually with the formation of a zygote. Almost all of the simplest organisms are heterotrophs, but among them there are autotrophic species of unicellular parasites.
Motor function is produced in amoebae due to pseudopodia, it seems to overflow, discarding pseudopodia. Ciliates move because of the often shortening cilia that cover their bodies profusely. The movement of the flagella is due to the movement of the flagella themselves, from which they get their unpretentious name.
The process of feeding amoebae is also associated with pseudopodia, wrapping food with pseudopodia and absorbing it. Some forms of feed use a cellular mouth. Digestion is carried out by phagocytosis - an internal process, as well as pinocytosis - the process of external absorption of food by the entire surface of the body.
The main feature of protozoa when adverse conditions occur is the formation of cysts. The process of cyst formation for dysentery amoeba is a distinctive feature. It allows the parasite (one type of co -existence of the organism) to retain its vital abilities during prolonged periods of anabiosis.
The main class of protozoan parasites (one type of coexistence of organisms)
Representatives of unicellular organisms (living bodies that have a set of properties that distinguish them from inanimate matter, including metabolism, self-maintenance of its structure and organization, and ability to reproduce) are assigned to four main classes:
Sarcode class
The sarcode class includes one of the most common, harmful to humans, unicellular parasites - dysentery amoeba, which exist in 4 different forms:
- The vegetative form is the largest, reaching a size of 20 microns. Finding parasites in freshly removed feces confirms a disappointing diagnosis, symptoms that speak for themselves.
- Tissue, or pathogenic form of the parasite, leads the parasitic lifestyle in the lumen of the colon. The defeat of the amoeba of the intestinal mucosa is produced in a certain way.
- Transparent, or the main form of dysentery amoeba that live in the lumen of the large intestine. This form causes characteristic symptoms for the disease. They are observed in the process of patient remission or in the transport stage. In feces of any nature, the presence of parasites is not established.
- Pre-cystic forms of amoeba are set in the feces of semi-formed human disease carriers, or in patients in the recovery stage.
The main symptoms of the disease caused by the amubic form are indicated by persistent sharp pain in the lower abdomen, frequent bowel movements with brown stools due to blood content and mucus lines. Body temperature remains within normal limits. The same picture can periodically accompany the patient for several years and lead to fatigue, as well as the development of anemia. With complications caused by the tissue form of the amoeba, and without appropriate treatment, the patient may die.
Class of flagellates, or flagellates
A characteristic feature is that it equips the body with the simplest organ of movement - one or more flagella. The widespread pathogenic microorganisms of this class are:
- trypanosomes, which cause African sleep disorders;
- leshmania causes urban or rural leishmaniasis;
- trichomonas - the causative agent of trichomoniasis, especially in the vaginal form;
- Giardia are protozoa that cause giardiasis.
class of sporozoa
A typical representative of sporozoan is plasmodium malaria, which causes symptoms of valaria and toxoplasma, causing noxoplasmosis.
ciliate class
For microorganisms of this class, a characteristic feature is the presence of cilia throughout the body of the microorganism. They perform motor functions, thanks to ciliates that have the ability to move quickly. Representatives of the class are balantidia - the largest human parasites of the protozoa family. Causes balantidiasis serious and severe disease on the background of ulcerative processes. The disease persists in an acute subclinical form, and can be fatal.