Mode of nutrition is saprophytic, parasitic or symbiotic. Most reproduction is asexual (mitosis). The remaining haploid nucleus will divide by mitosis producing an individual with two haploid nuclei. 3. have inert crystalline structure outside the living cell. It occurs through asexual spores called conidia. During zoospore formation, flagella are withdrawn and organism comes to rest. Lizards, few insects and some fishes reproduce in this way. This type of reproduction is not seen in mammals. This kind of asexual reproduction is seen in both plants and animals. Asexual reproduction seen in plants are of the following types: 9. Macrocystis pyrifera. - Life cycle shows alternation of generation. Asexual reproduction is by spores called conidia or sporangiospores or zoospores, Sexual reproduction is by oospores, ascospores and basidiospores. 12. (i) Mode of nutrition. Gonyaulax. Both asexual and sexual mode of reproduction is present in them. – Harmful Algae 5: 548-557. Asexual reproduction is by spores.called conidia or sporangiospores or zoospores, and sexual reproduction is by oospores, ascospores and basidiospores. Example: Euglena – The chief member of this group and regarded as the connecting link between animals and plants. Cause disease like AIDS, common cold, and potato spindle tuber disease. Reproduction in Dinoflagellates: (i) Asexual reproduction is commonly through cell division. Asexual reproduction through conidia Sexual reproduction absent Examples include Alternaria, Colletotrichum, and Trichoderma. … (ii) Mode of reproduction. Locomotory organelle. Organism Significance/ Importance/Role Mode of Nutrition Mode of asexual Locomotory organelle reproduction 1. However, a large number act as decomposers of leaf litter. Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes.The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the full set of genes of their single parent. Fritz L. & M. Nass (1992) Developement of the endoparasitic dinoflagellate Amoebophrya ceratii within host dinoflagellate species. They also have mixotrophic nutrition. E.g. Sexual reproduction takes place by ascospore formation : Asexual reproduction is absent. ... •Asexual spores of molds grouped by mode of development And yet, scientists recognize some real disadvantages to sexual reproduction. a.) bacteria and monerans, e.g. He named the kingdoms as Monera, Protista, Fungi, Plantae, and Animalia. Fragmentation is a mode of asexual reproduction which involves breaking the parent body into several fragments and each fragment develops into a new individual. Sexual reproduction: Zygotes can be similar in morphology (isogamous) or dissimilar (anisogamous or oogamous). Multiple Choice Questions form important part of competitive exams and NEET exam and if practiced properly can help you to get higher rank. Q.23. This group includes photosynthetic phytoplanktons, non-photosynthetic zooplanktons and disease causing parasites. Asexual reproduction takes place through conidia formation. Five kingdom classification –. Reproduction of Eukaryotes. It is also an exception because its, mode of nutrition is mixotrophic. The Different Modes of Reproduction in Plants Are Explained Below: - Reproduction. Seven types of asexual reproduction. He uses cell structure, thallus organization, mode of nutrition, reproduction, and phylogenetic relationships as his primary classification criteria. It occurs through asexual spores called conidia. Mammals Nulliparous:- Cant’s reproduce e.g (of a woman or female animal) That has not given … However, a large number act as decomposers of leaf litter. Reproduction: They may be vegetative (fission, fragmentation and budding), Asexual (occurs by formation of spores or mitospores) and sexual. Sex organs are absent but sexual reproduction takes place through plasmogamy. (i) Mode of nutrition. On the basis of characteristics, such as cell structure, mode of nutrition, presence of cell wall, etc., five kingdoms, Monera, Protista, Fungi, Plantae, and Animalia were formed. In protozoans, asexual reproduction occurs by binary fission, budding, or schizogony. Proposed by R.H. Whittaker (1969). Sexual reproduction is absent in deuteromycetes. - J. Phycol. Answer. (d) asexual reproduction. Gonyaulax catenella; ... Reproduction Asexual Reproduction In Sarcodina, asexual reproduction through binary fission is the primary mode of reproduction. The zygote may form a resting stage known as dinocyst or may remain motile; The … The slime moulds resemble both protozoa and the true fungi. T.O. It includes bacteria as well as blue-green algae. Sexual reproduction is absent in deuteromycetes. Figure 12.10 Gonyaulax, a motile armored dinoflagellate. A s c omyc e te s (S ac fu n gi ) They are saprophytic, decomposers, parasitic, or coprophilous. Many are symbionts with fungi, plants, or … Fig.1. In protozoans, asexual reproduction occurs by binary fission, budding, or schizogony. • The process of this reproduction is instant as compared to sexual reproduction. They produce spore within sporangia. Euglena. A motile algae. Sex organs are absent but sexual reproduction takes place through plasmogamy. During the sexual phase, two haploid cells called gametes In lower Organisms like protists and monerans, the organism or the parent cell divides into two, to give rise to new individuals. Depending on the species and environmental conditions, asexual and sexual reproduction occur in algae. (xii)Sexual reproduction is not observed. Gametes are isogamous or anisogamous or oogamous. This web site was designed by Laure Guillou and Fabrice Not (Biological station of Roscoff, CNRS, France). Sexual reproduction was an early evolutionary innovation after the appearance of eukaryotic cells. Q10 : Asexual reproduction is the only way of reproduction in deuteromycetes. Reproduction occurs by asexual (binary or multiple fission) and sexual reproduction … (iii) The life cycle involves zygotic meiosis in Ceratium, Gymnodinium and Woloszynskia. Diatoms are diploid thus involving gametic meiosis (diplontic life cycle). 3. Sexual reproduction: Zygotes can be similar in morphology (isogamous) or dissimilar (anisogamous or oogamous). (3) Association of … Amoeba (the parent cell divide into two to give rise to new individuals). • There is no involvement of gamete formation and fertilization. Answer: fission; budding; fragmentation; sporulation; regeneration However, a large number act as decomposers of leaf litter. It involves fusion of two different strains of hyphae. Host infected with the immature stages of parasite which multiply asexual reproduction. 21.2 Diversity of Protists. Cysts occur in a number of dinoflagellates. Cell division in itself is a mode of reproduction in protists, e.g. (b) The five kingdom classification is a mode of classification based on the following criteria. Main mode of asexual reproduction in diatoms. histolytica. Sexual reproduction is absent in Deuteromycetes. Cell division in itself is a mode of reproduction in protists, e.g. Entamoeba. Sexual reproduction is isogamous, anisogamous, or oogamous. Asexual reproduction is the only way of reproduction in deuteromycetes. Reproduction occurs by asexual (binary or multiple fission) and sexual reproduction … Paramecium. Spores (conidia) are produced exogenously on conidiophores. … Saxitocin. Both asexual and sexual modes of reproduction are found. (i) Mode of nutrition - They are obligate parasites on plants or are found on decaying matter such as wood. Asexual Reproduction Asexual reproduction occur by binary fission and endospore formation. Sexual reproduction is by conjugation. Apply 1.If I we’re given the chance, and have the means to do so, I would probably want to create a vaccine for HIV. Asexual reproduction takes place by zoospores (motile) or by aplanospores (non-motile). Asexual reproduction: Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. Sexual reproduction by Oospores, ascospores and basidiospores­ produced in fruiting bodies. Reproduction. vegetative means – fragmentation, fission and budding. The products of schizogony are called merozoites and they are stored in structures known as schizonts. Asexual reproduction occurs through asexual spores produced exogenously, such as conidia produced on conidiophores. 9. There are three steps of sexual cycle in fungi-Fusion of the protoplasm is known as plasmogamy. Asexual reproduction A single parent is capable of producing offsprings. (i) Mode of nutrition Some members are saprophytes while others are parasites. __________ is not a method of vegetative propagation. In schizogony , the nucleus of a cell divides multiple times before the cell divides into many smaller cells. (ii) Mode of reproduction. • In asexual reproduction, only one parent is involved. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Asexual reproduction is the only way of reproduction in deuteromycetes. Multiple Choice Questions form important part of competitive exams and NEET exam and if practiced properly can help you to get higher rank. b.) Asexual reproduction takes place through binary fission, plasmotomy, spores, cyst and sclerotium. The initial phase of growth was predominantly asexual, during which time the intracellular and extracellular phosphorus pools decreased steadily in the light and the dark. This group includes photosynthetic phytoplanktons, non-photosynthetic zooplanktons and disease causing parasites. 27. Dinophyceae reserve their food in the form of starch or fat. Gonyaulax. Algae refers to many phyla of protists that carry out photosynthesis. They have rigid cell walls containing agar or carrageenan, which are useful as food solidifying agents and as a solidifier added to growth media for microbes. Some members are saprophytes while others are parasites. A list of learning objectives and key ideas to help you guide classroom discussion 3.74A-C). ... such as Gonyaulax, produce potent toxins, which may kill fish and invertebrates outright or accumulate in the food chain, posing a hazard to humans eating shellfish and other seafood. 1 16 Sep 2016 4. Most reproduction is asexual (mitosis). Biological classification MCQ for NEET Pdf questions and answer are prepare for class 11 and NEET students. Asexual reproduction occurs by conidia, zoospore and sporangiospores. Sexual reproduction may be of isogamous, anisogamous, or oogamous type. 1. (ii) Mode of reproduction Asexual reproduction takes place commonly through fragmentation. Most have two flagella of unequal lentgth. So, the correct answer is option B. In protozoans, asexual reproduction occurs by binary fission, budding, or schizogony. The kingdoms defined by him were named Monera, Protista, Fungi, Plantae and. A spore possesses a cell wall of cellulose. 89. Significance/ Importance/Role. R.H. Whittaker proposed a Five Kingdom Classification in 1969. Sexual ... – A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 1a1309-ZDc1Z Paramecium 3. Dinoflagellates Reproduction. 2. Some members are saprophytes while others are parasites. There are more than 200,000 known species of protists with many more yet to be discovered. 1. Sexual reproduction is absent in deuteromycetes. (b) mode of nutrition. Eukaryotic DNA packaged as chromosomes in the nucleus. The maximum of melatonin is followed by a peak of 5-methoxytryptamine. They inhabit just about any area where water is found some or all of the time. Some members are saprophytes while others are parasites. - eg. Sexual reproduction is absent in deuteromycetes. Regeneration is the process of development of lost or damaged part. Rapid multiplication of dinoflagellates like Gonyaulax. Asexual reproduction seen in animals are of the following types: This method of reproduction is commonly used by bacteria and amoeba. The resulting dikaryon gives rise to a basidium. y They reproduce sexually varying from isogamy to oogamy. Reproduction in fungi occurs by- budding, fragmentation, and fission. Protists The kingdom Protista is the most diverse of all the five Eukaryotic kingdoms. Asexual reproduction by zoospores (motile) or by aplanospores (non-motile). Sexual spores are arranged in ascus with Ascospores in ascomycetes, whereas sexual spores are arranged in basidium in … Sexual reproduction is absent in Deuteromycetes. Toxopasma gondii. Asexual reproduction is common among single-celled organisms and in plants and animals with simple organisations. 32. (ii) Mode of reproduction. Asexual reproduction is common among single-celled organisms and in plants and animals with simple organisations. Kingdom Plantae It includes all eukaryotic chlorophyll-containing organisms known as plants. Four basidiospores are produced inside a basidium. (x) Asexual reproduction occurs by longitudinal binary fission. The unit of reproduction is commonly formed from the somatic cells of the parent. (xi)Under unfavourable condition the euglenoids form cysts to perennate the dry period. These are often referred to as clone. The flagellum is duplicated before cell division. These cells each acquire half of the theca (or cellulose plates) from. It is the infective part … However, a large number act as decomposers of leaf litter. Asexual reproduction is the only way of reproduction in deuteromycetes. Rapid multiplication of dinoflagellates like Gonyaulax. Asexual reproduction by spores-conidia, sporangiospores or zoospores. Have variety of methods of asexual reproduction. Sexual cycles involves the following steps-Plasmogamy, fusion of male and female gametes. Mode of Reproduction. Sexual reproduction – zygote can be similar or dissimilar in morphology: Through asexual spores called conidia and sexual spores are known as ascospores: By vegetation reproduction through budding. Asexual spores called conidia are produced in conidiophores. Q5. , The mycelium is septate and branched. Sexual reproduction takes place via gametangial copulation. Morphological and genetical similar individuals which are produced by Asexual mode of reproduction is known as clone. Development of different organisms from non -sexual reproductive units like fragments, buds, gemmules and spore is known as blastogenesis and asexual reproductive body is known as blastos. Ascospores ( sexual spores) produced in asci and are arranged in ascocarps. 1) Plantae 2) Fungi 3) Protista *4)Monera 3. In five kingdom system, the main basis of classification is. Biological classification Biological classification Biological classification is defined as the process of grouping the organisms according to certain similarities Linnaeus proposed the two kingdoms of classification. The daughter nuclei separates, cleaves cytoplasm centripetally in the middle till it divides parent protoplasm into two daughter protoplasm. Harmful as they release toxins which kill marine animals. The primary advantage of asexual reproduction is the fact that offspring can be successfully created without the need for a partnership. Triemer (1989) Ultrastructural aspects of sexual reproduction in the red tide dinoflagellate Gonyaulax tamarensis. Comparatively younger cell i.e., the cell with cap behaves as sporangium mother cell. 6. Asexual reproduction occurs by means of spores known as conidia, zoospores or sporangiospores. 3. The micronucleus will divide by meiosis; 3 of the 4 resulting nuclei will disintegrate as will the macronucleus. Question 8. Who is known as ‘Producers of the oceans’? 3. Cell division in itself is a mode of reproduction in protists, e.g. 2. Noctiluca, sea sparkle. It includes bacteria as well as blue-green algae. This dinoflagellate produces toxins that lead to the death of fishes. Asexual reproduction is a process of producing offspring that does not involve either meiotic cell division or syngamy, which is the fusion of two cells for reproduction. 5. It occurs over a short period of time without the need to develop the genetics to form a gender. Asexual reproduction is the primary form of reproduction for single-celled organisms such as archaea and bacteria. Their asexual reproduction takes place with the help of conidia. More complicated than that in prokaryotes. (3) Sexual reproduction is always biparental (4) Monocystis exhibits sporulation in favourable condition NEET & AIIMS 2018-19 M-CAPS-26 : ZOOLOGY (Medical-Classroom Assessment Practice Sheet) Topics covered : Types of Reproduction–Asexual reproduction, Sexual reproduction… green algae (approximately 17,000 species) Inhabit a variety of environments including oceans, freshwater, snowbanks, tree bark, and turtles’ backs. The nucleic acid present in the viruses is known as nucleoid. It is a brutal HIV. The maximum of melatonin is followed by a peak of 5-methoxytryptamine. (i) Mode of nutrition (ii) Mode of reproduction Ans (A) Phycomycetes - This group of fungi includes members such as Rhizopus, Albugo, etc. He named the kingdoms as Monera, Protista, Fungi, Plantae, and Animalia. Asexual reproduction takes place by means of zoospores (Fig. (i) Mode of nutrition. There are two modes of reproduction, sexual and asexual. Sexual reproduction occurs via basidiospore formation. Asexual reproduction takes place by motile zoospores or non-motile aplanospores. In ascomycetes, Asexual mode of reproduction is prominent by conidiospores. Most of Dinophyceae lived in marine water and few are fresh water. ... Gonyaulax. Asexual reproduction – by spores called conidia or sporangiospores or zoospores. 1) Structure of nucleus *2) mode of nutrition 3) Structure of cell wall 4) asexual reproduction 2. Asexual reproduction is the dominant form of reproduction. Gonyaulax. Mode of nutrition may be parasitic, ingestive, photosynthetic, saprophytic, mixotrophic etc. It involves fusion of two different strains of hyphae. Noctiluca is an exception in Dinoflagellates because: (i) It is colourless. Sexual reproduction is absent in deuteromycetes. There are advantages and disadvantages to both sexual and asexual reproduction. Asexual Reproduction. 2. c. The offspring are genetically identical to parent. The relative importance of sexual and asexual reproduction can vary greatly even between closely related taxa. Asexual reproduction is common among single-celled organisms and in plants and animals with simple organisations. Asexual reproduction is through zoospores or aplanospores. In asexual reproduction, only one parent is required to produce an offspring. Almost all prokaryotes undergo a type of asexual reproduction called binary fission. Mode of Reproduction. Mode of nutrition may be parasitic, ingestive, photosynthetic, saprophytic, mixotrophic etc. Reproduction – vegetative – fragmentation, fission and budding. 29. Thus, the offsprings are genetically and morphologically identical to one another and to their parent. Meiosis does not occur in asexual reproduction. However, a large number act as decomposers of leaf litter. Viruses possess an outer thin loose covering called envelope. The zoospores are multiflagellate and ovoid, pyriform or spherical in shape. Complete the table. materials are not organized into nucleus and contain naked DNA.Membrane bounded organelles are absent.Reproduction is asexual except gene recombination.Flagella may be present and are of single stranded.Example- Blue-green algae, Bacteria, etc. Harmful as they re- ... organisation, mode of nutrition, reproduction and phylogenetic relationships. b. Asexual reproduction only requires one parent. Fritz L., D.M. Sexual reproduction is absent in deuteromycetes. simplest single-celled organisms such as archaea, and bacteria, reproduce by binary fission.In Mode of nutrition* Mode of asexual reproduction. The various spores are produced in distinct structures called fruiting bodies. A reference list for more information about the organisms used in this activity. Mode of nutrition: Some members are saprophytes while others are parasites. sexual reproduction – by oospores, ascospores and basidiospores. NEET Masterclass in Biology 3 Biological Classification questions & solutions with PDF and difficulty level In which kingdom would you classify the archaea and nitrogen-fixing organisms, if the five-kingdom system of classification is used? (ii) Mode of reproduction Asexual reproduction is the only way of reproduction in deuteromycetes. bacteria and monerans, e.g. Gametes are similar in morphology (isogamous) or dissimilar (anisogamous or oogamous). Algae refers to many phyla of protists that carry out photosynthesis. Class of flatworms. 7. Algae, Bryophytes,Pteridophyte, Gymnosperms and Angiosperms. Photosynthetic euglenoids behave like heterotrophs in the dark, this mode of nutrition is known as mixotrophic. The first attempt of classification was made by Aristotle. Zygospores are formed by fusion of two gametes. Amoeba (the parent cell divide into two to give rise to new individuals). They are plant-like in the production of spores during reproduction and animal-like in the mode of nutrition and rheumatic organization. The They are called as imperfect fungi because perfect stage or sexual reproduction is absent. It appears to have been very successful because most eukaryotes are able to reproduce sexually, and in many animals, it is the only mode of reproduction. In protists, reproduction takes place by means of asexual and sexual methods. Harmful as they re- ... organisation, mode of nutrition, reproduction and phylogenetic relationships. green algae (approximately 17,000 species) Inhabit a variety of environments including oceans, freshwater, snowbanks, tree bark, and turtles’ backs. What are the characteristics of gametes produced by Ulothrix ? Asexual reproduction in fungi: 1 Fission: In binary fission a mature cell elongates and its nucleus divides into two daughter nuclei. ... 2 Budding: The cell wall bulge out and softens in the area probably by certain enzymes brought by vesicles. The protoplasm also bulge out in this region as small protuberance. 3 Fragmentation: More items... Bacteria are the most abundant micro-organism that can survive in all kinds of climate. The small animal which cannot mate with male organism have a benefit to reproduce by Asexual mode of reproduction and producing number of young ones without any cost and time expanding this is major advantage of Asexual mode of reproduction. - Reproduction – vegetative,asexual and sexual. bacteria and monerans, e.g. Asexual reproduction is the only way of reproduction in Deuteromycetes. For the most part, this has been shown to occur through simple binary fission where the cell divides to produce two daughter cells. Reproduction may be vegetative (fragmentation, fission or budding), asexual (conidia, sporangiospores or zoospores) or sexual reproduction by oospores, ascospore and basidiospores. Meiosis does not occur in asexual reproduction. 34. Give one word for the following from the given options. Alexandrium tamarense (=Gonyaulax tamarensis) formed cyst at 21 °C ... and that ratio may differ for different stages of reproduction or for different mode of reproduction in an alga (Mohsen et al. 30. Both sexual and asexual modes of reproduction occur. • Offspring growth is rapid in NEET Biology Biological Classification MCQs Set A with answers available in Pdf for free download. Protozoans that can be transmitted by inhaling dust of cat feces. The shift between sexual and asexual reproduction is Mating experiments revealed the existence of two presumed to play an important role in the regulation sexual types ( þ / ), which were enough to explain of bloom dynamics (Anderson et al. Ovoviviparity is seen in fishes like sharks. This means that they have both photosynthetic and saprobic type of nutrition as it is present in euglena. Asexual spores are absent. These are equivalent to the seeds of trees: forms resistant to the environment that, when the optimal conditions finally occur, germinate and create a new specimen of the fungus. In schizogony , the nucleus of a cell divides multiple times before the cell divides into many smaller cells. Four basidiospores are produced inside a basidium. (ii) Mode of reproduction. Illustrated information sheets for 12 organisms. It occurs through asexual spores called conidia. Asexual reproduction can happen much more quickly, and therefore is the predominant way of reproduction during optimal environmental conditions, but sexual reproduction is essential for species adaptation and survival because it allows for genetic recombination (i.e. However, a large number act as decomposers of leaf litter. Asexual reproduction in fungi: 1. ... Mode of reproduction Asexual reproduction takes place through the formation of zoospores (motile) or aplanospores (non-motile). In protozoans, asexual reproduction occurs by binary fission, budding, or schizogony. Find out the incorrect one- 1) Fragments of blue green algae are called Hormogonia. Mode of Reproduction: Fungi reproduce in a sexual and asexual way , always through the production of spores. The various spores are produced in distinct structures called fruiting bodies. Mode of reproduction: Asexual reproduction is the only way of reproduction in Deuteromycetes. The main criteria for classification used by him include cell structure, thallus organisation, mode of nutrition, reproduction … Sexual reproduction is rare and isogamous in Dinophyceae. 6. NEET Biology Biological Classification MCQs Set A with answers available in Pdf for free download. Binary Fission. Mouth-like opening on some protozoans. Thus, in these organisms cell division is itself a mode Of reproduction. Reproduction in dinoflagellates is primarily asexual through binary fission. These are Unicellular. Isogamy and anisogamy in ceratium. This type of reproduction occurs when new individuals are formed without the production of seeds or spores. Anderson & R.E. (1) Chief producers in oceans. Asexual reproduction by zoospores (motile) or by aplanospores (non-motile). More complex life cycles occur, more particularly with parasitic dinoflagellates. Rapid multiplication of dinoflagellates like Gonyaulax. A double cross wall is deposited in the middle to form two daughter cell. 42. (ii) Mode of reproduction. Mode of nutrition is saprophytic, parasitic or symbiotic. The life cycle usually involves asexual reproduction by means of mitosis, either through desmoschisis or eleuteroschisis. Mode of reproduction is always asexual through the formation of conidia. y The reproduction of diatoms is by asexual method, binary fission being most common mode. bacteria and monerans, e.g. Contributions or suggestions are very welcome and can be submitted either to Laure Guillou or to Fabrice Not.Laure Guillou or to Fabrice Not. a. Asexual reproduction occurs frequently when the environment is favorable to growth. Asexual Reproduction in Animals Asexual reproduction is common among single-celled organisms and animals with relatively simple organisation. Many are symbionts with fungi, plants, or … Question 10: Ascomycetes: saprophytic, decomposers, parasitic or coprophilous. The steps are (i) Plasmogamy : fusion of protoplasm of two motile or non- 4. Sporozoa that parasitizes a viable host cell. Melatonin exhibits a high-amplitude circadian rhythm characterized by a dramatic increase shortly after the onset of darkness. Answer: Diatoms. 10. Sexual Reproduction. The products of schizogony are called merozoites and they are stored in structures known as schizonts. Many reproduce sexually by forming gametes and zygotes. materials are not organized into nucleus and contain naked DNA.Membrane bounded organelles are absent.Reproduction is asexual except gene recombination.Flagella may be present and are of single stranded.Example- Blue-green algae, Bacteria, etc. The products of schizogony are called merozoites and they are stored in structures known as schizonts. 12. Reproduction in Organisms By :- Dr.Nirav R.Soni (M.Pharm,PGDIPR,PGDRD,GPAT,CAFÉ,Ph.D) 2. Five kingdom classifications Kingdom Monera The most important members of Monera are Bacteria. ... Gonyaulax catenella produces _____in sea water. Most viral diseases either have a cure or a vaccine, HIV on the other hand does not. In sexual reproduction, fertilization occurs through syngamy and conjugation. Some members are saprophytes while others are parasites. (a) structure of nucleus. Sexual reproduction is by conjugation. He uses cell structure, thallus organization, mode of nutrition, reproduction, and phylogenetic relationships as his primary classification criteria. Cellulose cell wall of thecal ... Pfisteria. Bacteria are the most abundant micro-organism that can survive in all kinds of climate. Euglena), cyst formation (e.g., Entamoeba), budding, sporulation, etc.