"Ciliated Protozoa: Vorticella" by bccoer is licensed under CC0 1.0
Definition of Ciliates
The term "ciliata" comes from the Latin cilia which means "little hair". Ciliates are protozoa that have a locomotion tool in the form of vibrating hairs (cilia). This vibrating hair is a characteristic of ciliates and functions as a means of locomotion and foraging for food. Ciliates are single-celled organisms (unicellular) with a fixed or unchanged shape.
There are about 8,000 types of ciliates that move with these cilia (shaking hairs) and most of them live in freshwater waters. Ciliates are divided into two groups based on the distribution of cilia, namely cilia on some cells only and cilia that cover all parts of the cell. Food Ciliates are microscopic bacteria and algae. Ciliates get their food by moving the cilia to cause a whirlpool effect so that food enters the whirlpool.
Ciliates have many specialized organelles including cilia (singular cilium), short hair-like structures on the outside of their bodies. As previously explained, there are cilia or cilia that cover the entire body surface or are only localized to certain body parts. In the Paramaecium genus , cilia cover the entire body surface.
A good coordination system in hair vibrates, causing Ciliates to move quickly, about one millimeter per second . Although only single-celled (unicellular), Paramaecium can respond to the surrounding environment well. If it encounters a hazardous chemical or barrier, the cell quickly retreats with cilia moving in a different direction.
Ciliates are excellent predators. Some ciliates, including Paramaecium and Didinium, are able to immobilize their prey by releasing needles called trichocysts that attach to their bodies. The prey is then carried into a mouth-like structure and digested in a vacuole which occasionally functions as a stomach.
When the process of digestion of food in ciliates has been completed, the waste products of metabolism will be excreted through exocytosis . In the ciliate body, excess water will accumulate in the vacuole which periodically (periodically) contracts to empty the fluid through an opening called the anal pore .
Characteristics of Ciliates
Ciliata or Ciliophora has several characteristics or characteristics that distinguish it from the three other types of Protozoa . Here the author describes the characteristics of Ciliates in general.
■ Moving with cilia or hair shakes.
■ It is a single-celled organism (unicellular).
■ Having a permanent body shape or unchanged.
■ Characteristically heterotrophic, meaning that living with other organisms prey because they can not make their own food.
■ Generally microscopic, but there are also species with size up to 3 mm so that it can be observed with the naked eye.
■ Body shape assortment, such as an oval shape, slippers, a bell, a funnel and so forth.
■ Most live in waters such as swamps, rice paddies and watery places that are rich in organic matter.
■ Living independently (solitary), parasites, or symbionts in the gut of vertebrates.
■ Have a contractile vacuole which serves to regulate cell osmotic pressure (osmoregulation).
■ Has two kinds of nucleus (center) within a single cell, which is makronukleus role in metabolism and asexual reproduction (vegetative), and micronucleus that play a role in sexual reproduction (generative).
Ciliates Classification
Based on the distribution or distribution pattern of cilia (shaking hair), Ciliates are grouped into two groups, namely Ciliates with cilia that are spread evenly over the entire body surface (ex. Coleps, Bursaria, Paramaecium, Stentor, Calpoda and Prorodon) and Ciliates with localized cilia. or only found in certain body parts (ex. Acineto, Didinium, Stylonichia, and Vorticela). For clarity, please look at the following image.
Meanwhile, based on their way of life, Ciliates are divided into four groups, namely Holotricha, Suctoria, Peritrichia, and Spirotichia. The following is an explanation of each of these ciliate groups.
■ Holotrichia , is a group Ciliate living with swim freely, for example on Paramaecium and Didinium.
■ Suctoria , is Ciliate group that has tentacles and usually live attached to the substrate, for example Vorticella.
■ Peritrichia , is Ciliate groups that live in colonies and are usually spherical or oval, for example Nyctoterus ovalis .
■ Spirotrichia , is a group Ciliate shaped like a trumpet and a sedentary life in freshwater bergenang or flow, for example, Stentor and Euplotes.
How to Reproduce Ciliates
Ciliates can reproduce in two ways, namely sexually (mating) through conjugation and asexually (not mating) through transverse binary fission . Conjugation in Ciliates does not produce new daughter cells, but after conjugation, the cell divides to produce four identical daughter cells which are better able to survive the unfavorable environmental conditions.
Binary fission in Ciliates can be observed when one cell divides into 2, then into 4, 8 and so on. This division begins with the splitting of the micronucleus and is followed by the division of the macronucleus. Then 2 daughter cells will be formed after the replacement of the plasma membrane. You need to know that each of the daughter cells is identical and the other cell apparatus has two nuclei and cytoplasm.
Examples and Roles of Ciliates in Life
Similar to Rhizopoda, organisms belonging to the Ciliata class also have various important roles for human life, both harmful and beneficial. Then what is the role of this Ciliata? Here are some examples of Rhizopod organisms and their role in life.
■ Balantidium coli is a protozoan parasite that lives in the intestines of humans and is the only species that cause disease Siliata. These ciliates can cause sores (inflammation) called balantidiasis . Balantidiasis is a type of stomach disorder such as bloody diarrhea. The intermediate host of this disease is pigs, then it is transmitted through food or drink contaminated by pig manure containing Balantidium coli .
■ Paramaecium often called animal slippers for cell shape resembles a slipper. It is a single cell organism usually less than 0.25 mm in length. Paramecium has two nuclei, a large nucleus called the macronucleus and two smaller nuclei called the micronucleus. Without macronucleus Paramecium cannot live and without micronucleus Paramecium cannot reproduce. Reproduction is done asexually by binary fission. Sometimes also reproduce sexually by conjugation. Paramecium is found in abundance in freshwater bodies almost all over the world. Several species of Paramecium are found living in the sea. Paramecium caudatum is one type of freshwater Paramecium that is widely used for research.
■ Nyctoterus ovalis is a species that lives ciliate parasites in the intestines of cockroaches.
■ Stentor is shaped like a trumpet Ciliate and settle somewhere.
■ Vorticella is shaped like a bell Ciliate long-stemmed with straight or spiral shape that comes cilia (hairs vibrate) around his mouth.
■ Didinium is Ciliate that act as predators in aquatic ecosystems, ie predators Paramaecium.
■ Stylonichia is Ciliate that looks like a snail or oval, cilianya group called cirri . Stylonichia is commonly found on the surface of leaves that are submerged in water.
