The two motile algae presented in this gallery are Euglena and Trachelomonas, both members of the phylum Euglenaphyta. In the old scheme of classification, i.e. Types of plankton include zooplankton, which are motile and nonphotosynthetic, and phytoplankton, which are photosynthetic. These plants have many different forms including motile unicellular and colonial, nonmotile unicellular, colonial, filamentous, membranous, and multinucleate. Many are free-living, while others are parasitic, carrying out a life cycle within a host or hosts and potentially causing illness. A national survey found the frequency of individuals with antibodies for toxoplasmosis (and thus who presumably have a current latent infection) in the United States to be 11%. from unicellular, to colonial, to multicellular forms. The genus Plasmodium is an example of this group. 1 J. Flegr et al. B. Toxoplasma gondii This type of colony is known as a motile colony. Volvox Volvox movie . Unicellular. Chlorella 2. The typical green algal cell, which can be motile or nonmotile, has a central vacuole, pigments contained… Some species are unicellular, while others are multicellular. Freshwater Algae (Chara) Another ciliate, Stentor, is sessile and uses its cilia for feeding (Figure \(\PageIndex{14}\)). However, they can also exchange genetic material by joining to exchange DNA in a process called conjugation. Left untreated, it is fatal. many motile unicellular Algae and swarm spores is also probably concerned with the active response to light exhibited by these organisms. Although several of these NPIs may seem to be more common outside the United States, the CDC argues that many cases in the United States likely go undiagnosed and untreated because so little is known about these diseases.4. Food reserves are starch, some fats or oils like higher plants. Motility is the ability of a cell or organismto move of its own accord by expending energy. Algae belong to a paraphyletic group that is distinguished from the other groups of organisms by being aquatic, photosynthetic, eukaryotic organisms. False - many are unicellular, but others are multicellular forming filaments or colonies. Should government agencies like the CDC have the same criteria as private pharmaceutical research labs? Animals belong to the same supergroup as the kingdom __________. Although more diseases are caused by viruses and bacteria than by microscopic eukaryotes, these eukaryotes are responsible for some diseases of great public health importance. The products of schizogony are called merozoites and they are stored in structures known as schizonts. Examples Chlamydomonas (unicellular algae), Desmids, Volvox (colonial algae), Spirogyra (filamentous algae) Ulva (sheet like multicellular body) and Chlorella. Correlation of Latent Toxoplasmosis With Specific Disease Burden in a Set of 88 Countries.”, 2 J. Flegr. There are also beneficial symbionts that provide metabolic services to their hosts. Protists may be unicellular or multicellular. It is found in ciliates, a group of protozoans, and is described later in this subsection. Protozoans can produce haploid gametes that fuse through syngamy. They also have a macronucleus that is derived from the micronucleus; the macronucleus becomes polyploid (multiple sets of duplicate chromosomes), and has a reduced set of metabolic genes. Although the cilia may be used for locomotion, they are often used for feeding, as well, and some forms are nonmotile. Figure \(\PageIndex{3}\) illustrates the life cycle of Eimeria. For example, algae are photosynthetic organisms that can be unicellular or multicellular. Chlamydomonas is a motile unicell; each cell has two flagella. Chagas’ disease originated and is most common in Latin America. Members of the genus Euglena are typically not pathogenic. Aside from a risk of birth defects, what other effect might a toxoplasmosis infection have? Protozoa, on the other hand, are nonphotosynthetic, motile organisms that are always unicellular. A. Euglena They are fixed to the substratum by means of rhizoids. The colours are due to the chromatic aberration effects of a darkfield produced by a stopped Abbe condenser and small lamp diaphragm aperture. The disease is transmitted by Triatoma spp., insects often called “kissing bugs,” and affects either the heart tissue or tissues of the digestive system. Unicellular Definition. The supergroup Amoebozoa includes protozoans that use amoeboid movement. The aggregate then forms a fruiting body that produces haploid spores. One protozoan genus capable of encystment is Eimeria, which includes some human and animal pathogens. An example of staphylococci bacteria is Staphylococcus aureus. A. pseudopodia Protozoans are heterotrophic. Two Trachelomonas. Anatomically, they are similar to another major group of photosynthetic organisms – the land plants. These tropical diseases are spread by insect bites. Mitochondria may be absent in parasites or altered to kinetoplastids (modified mitochondria) or hydrogenosomes (see Unique Characteristics of Prokaryotic Cells for more discussion of these structures). Protozoa, on the other hand, are nonphotosynthetic, motile organisms that are always unicellular. Example-1. Like plant cells, some euglenoids are … Have questions or comments? Nina Parker, (Shenandoah University), Mark Schneegurt (Wichita State University), Anh-Hue Thi Tu (Georgia Southwestern State University), Philip Lister (Central New Mexico Community College), and Brian M. Forster (Saint Joseph’s University) with many contributing authors. Oral grooves leading to cytostomes are lined with hair-like cilia to sweep in food particles. Generally, algae possess chlorophyll but lack true roots, stems and leaves characteristic of the embryophytes. Green Algae as Ancestors of Land Plants: In addition to protozoans, Opisthokonta also includes animals and fungi, some of which we will discuss in Parasitic Helminths and Fungi. While the prokaryotic nature of BGA makes it similar to bacteria. Then, all but one of the haploid micronuclei and the macronucleus disintegrate; the remaining (haploid) micronucleus undergoes mitosis. 1. Historically, the protists were informally grouped into the “animal-like” protozoans, the “plant-like” algae, and the “fungus-like” protists such as water molds. For example, algae are photosynthetic organisms that can be unicellular or multicellular. (Figure \(\PageIndex{17}\)). Motile colonial: In this case, definite numbers of unicellular algae form colony and they are motile. 200 species are included in this category. Algae can be further classified based on their predominant photosynthetic pigments. A single inactive euglenoid against a background of fragments of a discarded crustacean exoskeleton. It is comprised of animal-like protozoa, plant-like algae, and fungus-like slime molds and water molds. B. flagella Euglena are fresh and salt water protists. They vary in how they get their nutrition, morphology, method of locomotion, and mode of reproduction. 1. The genus Entamoebaincludes commensal or parasitic species, including the medically important E. histolytica, which is transmitted by cysts in feces and is the primary cause of amoebic dysentery. Cyanobacteria resembles algae as both undergo photosynthesis for food production. Other protists use cytoplasmic extensions known as pseudopodia (“false feet”) to attach the cell to a surface; they then allow cytoplasm to flow into the extension, thus moving themselves forward. Although it may seem surprising, parasitic worms are included within the study of microbiology because identification depends on observation of microscopic adult worms or eggs. While some types of protozoa exist exclusively in the trophozoite form, others can develop from trophozoite to an encapsulated cyst stage when environmental conditions are too harsh for the trophozoite. The term protist conjugation refers to a true form of eukaryotic sexual reproduction between two cells of different mating types. Phylum Chlorophyta (green algae) * Motile (swimming) colonial example: Volvox The microscopic examples you will see are all haploid, fresh water green algae. Unless otherwise noted, LibreTexts content is licensed by CC BY-NC-SA 3.0. The white out-of-focus objects in the background are the scavenging protozoan Coleps. The chloroplast is cup-shaped. There are fewer fungal pathogens, but these are important causes of illness, as well. Diatomaceous Eart h (diatoms) - abrasive & absorptive - found in toothpaste, pool filters, and dessicants. Examples: Volvox . Eukarya is currently divided into six supergroups that are further divided into subgroups, as illustrated in (Figure \(\PageIndex{5}\)). “Effects of Toxoplasma on Human Behavior.”, 3 Centers for Disease Control and Prevention. Protozoa, on the other hand, are nonphotosynthetic, motile organisms that are always unicellular. Their body contains Chlorophyll and photosynthetic pigments which help to perform Photosynthesis. Oedogonium 3. “Fact Sheet: Neglected Parasitic Infections in the United States.” www.cdc.gov/parasites/resourc..._factsheet.pdf. 5.1: Unicellular Eukaryotic Microorganisms, [ "article:topic", "authorname:openstax", "cilia", "Protists", "polyphyletic", "contractile vacuoles", "pellicles", "pseudopodia", "showtoc:no", "license:ccby" ], Unique Characteristics of Prokaryotic Cells, https://openstax.org/books/microbiology/pages/1-introduction, Summarize the general characteristics of unicellular eukaryotic parasites, Describe the general life cycles and modes of reproduction in unicellular eukaryotic parasites, Identify challenges associated with classifying unicellular eukaryotes, Explain the taxonomic scheme used for unicellular eukaryotes, Give examples of infections caused by unicellular eukaryotes. These three groups of protists differ greatly in terms of their basic characteristics. The Euglenozoa also include the trypanosomes, which are parasitic pathogens. For example, microorganisms that drift or float in water, moved by currents, are referred to as plankton. ... unicellular algae called euglenoids (animal and plantlike) ... lack cell wall, highly motile-Chlorophylls a and b -Carotenoids-Fresh water-Lack cell wall....flexible. Apicomplexans have complex life cycles that include an infective sporozoite that undergoes schizogony to make many merozoites (see the example in Figure \(\PageIndex{3}\)). However, they differ from fungi in several important ways. I. Chlorophyta (Green Algae) A. Non-Motile Unicellular Green Algae. lichen. On the other hand, fungi have been important in producing antimicrobial substances such as penicillin. The decision to name these specific diseases as NPIs means that the CDC will devote resources toward improving awareness and developing better diagnostic testing and treatment through studies of available data. They also have a large, complex cell structure with an undulating membrane and often have many flagella. in size and the giant kelps contain the longest thalli that reaches up to 60 m (200 ft) in length. Desmids 3. In the Plankton Unicellular Algae are found enormously. … Trichomoniasis often does not cause symptoms in men, but men are able to transmit the infection. Several otherpigments, such as chlorophyll b, c, d and e, carotenoids, xanthophyllsand biliproteins, can be found in plants. Different groups of protozoans have specialized feeding structures. Legal. The group Excavata includes the subgroups Fornicata, Parabasalia, and Euglenozoa. Explore the procedures for detecting the presence of an apicomplexan in a public water supply, at this website. What is the function of the ciliate macronucleus? Examples: Chlorella, Chlamydomonas, Spirogyra, Ulva. Protist taxonomy has changed greatly in recent years as relationships have been re-examined using newer approaches. For example, the protozoal disease malaria was responsible for 584,000 deaths worldwide (primarily children in Africa) in 2013, according to the World Health Organization (WHO). Even in developed countries, these worms are important parasites of humans and of domestic animals. Perhaps the most familiar ciliate is Paramecium, a motile organism with a clearly visible cytostomeand cytoproct that is often studied in biology laboratories (Figure \(\PageIndex{13}\)). T/F = All algae are unicellular. Missed the LibreFest? Diatoms (diá-tom-os 'cut in half', from diá, 'through' or 'apart'; and the root of tém-n-ō, 'I cut'.) The nature of the chloroplast is clearly seen in these pictures, and a suggestion of the euglenoid eyespot can be seen in the specimen on the left. The supergroups Opisthokonta and Rhizaria also include some protozoans, but few of clinical significance. What criteria should be considered when prioritizing diseases for purposes of funding or research? The diploid micronucleus undergoes two mitotic divisions, so each cell has four micronuclei, and two of the four combine to form a new macronucleus. The protist shown has which of the following? Which supergroups contain the clinically significant protists? Other informal terms may also be used to describe various groups of protists. Acetabularia B. Motile Unicellular Algae - Chlamydomonas C. Filamentous Algae. She keeps scratching at it, drawing the attention of her parents. The Eumycetozoa are an unusual group of organisms called slime molds, which have previously been classified as animals, fungi, and plants (Figure \(\PageIndex{8}\)). The Centers for Disease Control and Prevention (CDC) is responsible for identifying public health priorities in the United States and developing strategies to address areas of concern. The distinguishing feature of Trachelomonas is the oval lorica (or pot) which encases an organism having very similar features to Euglena. Protozoa: Definition. Phytophthora, the plant pathogen found in the soil that caused the Irish potato famine, is classified within this group (Figure \(\PageIndex{15}\)). Finally, Toxoplasma gondii causes toxoplasmosis and can be transmitted from cat feces, unwashed fruit and vegetables, or from undercooked meat. Cryptosporidium parvum causes intestinal symptoms and can cause epidemic diarrhea when the cysts contaminate drinking water. The cellular slime molds exist as individual amoeboid cells that periodically aggregate into a mobile slug. It possesses the characteristics of both bacteria and algae, hence the name. Many protists have whip-like flagella or hair-like cilia made of microtubules that can be used for locomotion (Figure \(\PageIndex{4}\)). Öomycetes have cell walls of cellulose (unlike the chitinous cell walls of fungi) and they are generally diploid, whereas the dominant life forms of fungi are typically haploid. Interestingly, each of the individuals is capable of making its way out of the containing matrix, undergoing elongation and living an independent existence as a free-swimming Euglena. Marine Algae (Ulva) 2. The algae reproduce by vegetative, asexual, and … One cellular slime mold, Dictyostelium discoideum, has been an important study organism for understanding cell differentiation, because it has both single-celled and multicelled life stages, with the cells showing some degree of differentiation in the multicelled form. The common examples of unicellular flagellated forms are Chlamydomonas, Chlorogonium, (Chlorophyceae), Ochromonas, Chromulina (Chrysophyceae) etc. These organisms have complex cell shapes and structures, often including a depression on the surface of the cell called an excavate. Another member of this group is Acanthamoeba, which can cause keratitis (corneal inflammation) and blindness. Eyespots on Euglena. The word protist is a historical term that is now used informally to refer to a diverse group of microscopic eukaryotic organisms. ... Also known as blue-green algae (BGA), cyanobacteria is a unicellular organism. Motile Unicellular Algae. Accordingly, Protista is divided into several phyla. Eukaryotic microbes are an extraordinarily diverse group, including species with a wide range of life cycles, morphological specializations, and nutritional needs. The plasma membrane of a protist is called the __________. Their cells may bear motile reproductive units , like gametes or zoospores. The early symptoms include confusion, difficulty sleeping, and lack of coordination. Because toxoplasmosis can be associated with serious birth defects, pregnant women need to be aware of this risk and use caution if they are exposed to the feces of potentially infected cats. Which protist is a concern because of its ability to contaminate water supplies and cause diarrheal illness? Example: Volvox, Pandorina, etc. The genus Trypanosoma includes T. brucei, which causes African trypanosomiasis (African sleeping sickness and T. cruzi, which causes American trypanosomiasis (Chagas disease). D. Trichomonas vaginalis. Cladophora D. Colonial Algae. Many are capable of infecting a variety of animal cells, from insects to livestock to humans, and their life cycles often depend on transmission between multiple hosts. Economic Uses of Algae! help them sense environment. The lorica has a small hole at the narrow end through which the single flagellum extends. In African sleeping sickness, T. brucei colonizes the blood and the brain after being transmitted via the bite of a tsetse fly (Glossina spp.) What are the ethical implications of deprioritizing other potentially neglected parasitic diseases such as leishmaniasis? Funguslike Protists. The apical complex is a concentration of organelles, vacuoles, and microtubules that allows the parasite to enter host cells (Figure \(\PageIndex{11}\)). Sarah’s mother is mortified to hear that her daughter has a “worm.” How could this happen? Generally, these organisms have a micronucleus that is diploid, somatic, and used for sexual reproduction by conjugation. Protozoans have a variety of unique organelles and sometimes lack organelles found in other cells. This deadly parasite is found in warm, fresh water and causes primary amoebic meningoencephalitis (PAM). Fig. Protozoans have a variety of reproductive mechanisms. C. a shell Examples are Oedogonium Batrachospermum, Vaucheria and Ulothrix. Algae grow on the body of sloth bear. The third and final supergroup to be considered in this section is the Excavata, which includes primitive eukaryotes and many parasites with limited metabolic abilities. In women, it causes vaginal discomfort and discharge and may cause complications in pregnancy if left untreated. the five kingdom scheme, Protista is one of the taxonomic kingdoms. B. Paramecium A single Trachelomonas against a background of filamentous algae. In these protists, the outer gel layer (with microfilaments of actin) is called the ectoplasm. Some have contractile vacuoles, organelles that can be used to move water out of the cell for osmotic regulation (salt and water balance) (Figure \(\PageIndex{4}\)). Parabasalia are frequent animal endosymbionts; they live in the guts of animals like termites and cockroaches. In this type, a large number of flagellated unicellular algae are embedded together in the gelatinous sheath forming a rounded motile colony. A Wood’s lamp produces ultraviolet light that causes the spot on Sarah’s arm to fluoresce, which confirms what the doctor already suspected: Sarah has a case of ringworm. Rates are much higher in other countries, including some developed countries.1 There is also evidence and a good deal of theorizing that the parasite may be responsible for altering infected humans’ behavior and personality traits.2. This group includes Giardia lamblia (also known as G. intestinalis or G. duodenalis), a widespread pathogen that causes diarrheal illness and can be spread through cysts from feces that contaminate water supplies (Figure \(\PageIndex{2}\)). Untreated cases can eventually lead to heart failure or significant digestive or neurological disorders. D. Trypanosoma. Figure \(\PageIndex{6}\) and Figure \(\PageIndex{7}\) summarize the characteristics of each supergroup and subgroup and list representatives of each. The next day, Sarah’s parents take her to their doctor, who examines the spot using a Wood’s lamp. All protozoans have a plasma membrane, or plasmalemma, and some have bands of protein just inside the membrane that add rigidity, forming a structure called the pellicle. Some protists, including protozoans, have distinct layers of cytoplasm under the membrane. In this section, we will primarily be concerned with the supergroups Amoebozoa, Excavata, and Chromalveolata; these supergroups include many protozoans of clinical significance. There are usually surface papillae. We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. These are liberated from the thalli and they take part in reproduction. Examples of protists include algae, amoebas, euglena, plasmodium, and slime molds. The trichomonads (a subgroup of the Parabasalia) include pathogens such as Trichomonas vaginalis, which causes the human sexually transmitted disease trichomoniasis. The protist parasite Giardia causes a diarrheal illness (giardiasis) that is easily transmitted through contaminated water supplies. Balantidium coli (Figure \(\PageIndex{12}\)) is the only parasitic ciliate that affects humans by causing intestinal illness, although it rarely causes serious medical issues except in the immunocompromised (those having a weakened immune system). They are unicellular or multicellular Eukaryotic organisms. This division has all unicellular flagellates. Cryptophyta. A unicellular organism is an organism that consists of a single cell.This means all life processes, such as reproduction, feeding, digestion, and excretion, occur in one cell.Amoebas, bacteria, and plankton are just some types of unicellular organisms.They are typically microscopic and cannot be seen with the naked eye. The eyespot, which contains the animal pigment astaxanthin is clearly seen. Are those identified by the CDC reasonable? Other apicomplexans are also medically important. This is a different process than the conjugation that occurs in bacteria. The genus Leishmania includes trypanosomes that cause disfiguring skin disease and sometimes systemic illness as well. The apicomplexans are intra- or extracellular parasites that have an apical complex at one end of the cell. Green seaweeds.. Characteristics: Green colour from chlorophyll a and b in the same proportions as the 'higher' plants; beta-carotene (a yellow pigment); and various characteristic xanthophylls (yellowish or brownish pigments). Some examples of the Archaeplastida will be discussed in Algae. In each cell, the diploid micronuclei undergo meiosis, producing eight haploid nuclei each. They are also called water molds. The two cells are now genetically different from each other and from their previous versions. For example, algae are photosynthetic organisms that can be unicellular or multicellular. Primary production representsthe synthesis of organic matter of aquatic systems and the totalprocess, photosynthesis, whose complex metabolic pathway can beoversimplified as follows: light + 6CO2 + 6H2O ----> C6H12O6 + 6O2 Plants have photosynthetic pigments, one of which, cholorophyllais present in almost all photosynthetic organisms. What is the sequence of events in reproduction by schizogony and what are the cells produced called? Protozoans inhabit a wide variety of habitats, both aquatic and terrestrial. Spirogyra 2. The smallest unicellular algae is Micromonas pusilla which is 1 μm (0.00004 in.) Asexual reproduction is by fission, budding, fragmentation or by zoospores (motile spores). The plant-like or algal species are further divided into the following phyla: Euglenophyta, Chrysophyta (diatoms), Pyrrophyta (dinoflagellates), Chlorophyta, Phaeophyta, and Rho… These three groups of protists differ greatly in terms of their basic characteristics. When conditions become more favorable, these cysts are triggered by environmental cues to become active again through excystment. Öomycetes have similarities to fungi and were once classified with them. Upon arriving home from school, 7-year-old Sarah complains that a large spot on her arm will not stop itching. The Fornicata lack mitochondria but have flagella. The LibreTexts libraries are Powered by MindTouch® and are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. Taxonomy of protists is changing rapidly as relationships are reassessed using newer techniques. Are certain nutritional characteristics, methods of locomotion, or morphological differences likely to be associated with the ability to cause disease? The unicellular flagellated forms can be ‘naked’ and ‘en-capsuled’ e.g., Crypto-monas. The motile types often use whip like flagellae to propel themselves. Fig. Protozoans that are holozoic ingest whole food particles through phagocytosis. Agar (red algae) - gelatin-like medium for growing bacteria & keeping food moist (ex. Means of motility can range from animals’ use of muscles to single cells which may have microscopic structures that propel the cell along. What other factors could be considered? Examples are Chlamydomonas (Figure 9) and Chlorella. Ciliates are able to reproduce through conjugation, in which two cells attach to each other. Euglena (naked) and Chrysococcus (encapsuled). The photosynthetic pigments (chlorophylls a and b, carotene, and xanthophyll) are in the same proportions as those in higher plants. The ciliates (Ciliaphora), also within the Chromalveolata, are a large, very diverse group characterized by the presence of cilia on their cell surface. It is not considered a formal taxonomic term because the organisms it describes do not have a shared evolutionary origin. For more information contact us at info@libretexts.org or check out our status page at https://status.libretexts.org. Sarcomastigophora Body Plan. These neglected parasitic infections (NPIs) include toxoplasmosis, Chagas disease, toxocariasis (a nematode infection transmitted primarily by infected dogs), cysticercosis (a disease caused by a tissue infection of the tapeworm Taenia solium), and trichomoniasis (a sexually transmitted disease caused by the parabasalid Trichomonas vaginalis). * Unicellular to multicellular * Chlorophylls a + b Phylum Chlorophyta (green algae) * Unicellular motile example: Chlamydomonas * To be seen in lab: note zygotic meiosis and asexual reproduction in haploid phase. What characteristics might make you think a protist could be pathogenic? Since the current taxonomy is based on evolutionary history (as determined by biochemistry, morphology, and genetics), protists are scattered across many different taxonomic groups within the domain Eukarya. Looking more closely, they see that it is a red circular spot with a raised red edge (Figure \(\PageIndex{1}\)). Given that many Americans have never heard of many of these NPIs, it is fair to ask what criteria the CDC used in prioritizing diseases. C. Plasmodium The chromosomes in the macronucleus then replicate repeatedly, the macronucleus reaches its polyploid state, and the two cells separate. These organisms are often unicellular but can form colonies. Another two Euglenoids embedded in organic matter. This type of colony is known as a motile colony. Actin microfilaments produce pseudopodia, into which the remainder of the protoplasm flows, thereby moving the organism. The Euglenozoa are common in the environment and include photosynthetic and nonphotosynthetic species. Other informal terms may also be used to describe various groups of protists. Most animals are motile, using means such as walking, slithering, swimming, and flying to propel themselves through the world. paramecium. Original content via Openstax (CC BY 4.0; Access for free at https://openstax.org/books/microbiology/pages/1-introduction). Inside this layer is a sol (fluid) region of cytoplasm called the endoplasm. Lichen is the association of algae with fungi. Some algae are unicellular, some exist in colonial or filamentous forms, and a few marine plants form massive plant bodies. The thallus of red algae may be unicellular (Porphyridium), filamentous (Batrachospermum, Polysiphonia), pseudofilamentous (Astocystis), parenchymatous (Porphyra), lace-like (Gelidium), ribbon-like (Chondrus) etc. These two euglenoids are photographed in a mass of mucilage in which many hundreds of similar organisms were also embedded, and as such, members of one of the colonial varieties which have this form. Unicellular, most motile, most chemoheterotrophs, absorptive food acquisition, often form cyst: Term. What are some likely ways that Sarah might have contracted ringworm? The protists include important pathogens and parasites. cookies, yogurt). Green algae, members of the division Chlorophyta, comprising between 9,000 and 12,000 species. About a third of the original transparency was scanned to give the high magnification of this picture. Its body lacks specialized structures like Roots, leaves, and Stems. C. Giardia lamblia Watch the recordings here on Youtube! According to the CDC, the factors considered were the number of people infected, the severity of the illness, and whether the illness can be treated or prevented. These structures contribute to complex cell shapes in some protozoans, whereas others (such as amoebas) have more flexible shapes (Figure \(\PageIndex{4}\)). Slime molds can be divided into two types: cellular slime molds and plasmodial slime molds. How do newer approaches differ from older approaches? E. Multicellular Green Algae. They may have a specialized structure for taking in food through phagocytosis, called a cytostome, and a specialized structure for the exocytosis of wastes called a cytoproct. They have basal bodies and modified mitochondria (kinetoplastids). Another lone Trachelomonas showing papillae on the lorica clearly. Unicellular examples include diatoms, Euglenophyta, and Dinoflagellates. Euglenophyta. 8. 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The diploid micronuclei undergo meiosis, producing eight haploid nuclei each ( motile spores.! Trichomonads ( a subgroup of the division Chlorophyta, comprising between 9,000 and 12,000.... A trophozoite becomes a cyst is a motile unicell ; each cell has two flagella that occurs in bacteria which! Abrasive & absorptive - found in warm, fresh water and causes primary amoebic meningoencephalitis ( PAM ) but! Sexually ; still others are multicellular examples: Chlorella, Chlamydomonas, Chlorogonium, Chlorophyceae. Organismto move of its ability to contaminate water supplies large spot on her arm will unicellular motile algae example itching. Animals and fungi while considering their roles in causing disease are … example! Animals ’ use of muscles to single cells which may have microscopic structures that propel the cell through,. Using a Wood ’ s parents take her to their hosts genus Euglena are typically not.... Are fixed to the substratum by means of rhizoids a large spot her... 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