Division CHRYSOPHYTA (Golden brown algae):
Mainly unicellular or colonial, filamentous forms are unusual. Motile cells contain two equal or unequal flage present on anterior end. Longer one contains stiff hairs and shorter is smooth. Cell wall is composed of pectin and silica or scales of carbonate. Chloroplasts are intensely lobed. Principal pigments are chlorophyll a, c, and carotenoids similar to B-carotene, fucoxanthin diatoxantin and neofucoxanthin. Storage products are mostly oil droplets, and true starch is not present but glucan granules or leucosin are present.
Sexual reproduction is unusual. Many common features are formation of resting cysts, resting spore (statspores), with silica walls. Cysts are formed as result of asexual or sexual reproduction. Golden-brown algae are spread in marine and fresh water habitats, and in fast flowing mountain streams. Marine coccolithophorides are liable for structure of chalk beds on bottom of sea. For e.g.: Chromulina, Symira, Ochromonas, Dinobryon and Mallomoanas.
Division EUGLENOPHYTA (Euglenoids):
Many euglenoids are simple unicellular motile flagellates. They do not have firm cell wall, and have features lime protozoans. They contain the contractile vacule. Cell surface is pellicle (thin membrane) and contains helical; knob like projections. Cell shape alters continually (eulenoid-movements).
Chloroplasts illustrate variety of shapes like discoid, ribbon like or stellate. Cells are biflagellate but only one flagellum comes out anteriorly. Photosynthetic pigments found in plastids comprise chlorophyll a, b and carotenoids including B-carotene. Few euglenoids are also colorless. The form of starch-paramylon is present as distinct granules. Oil droplets and polyphosophate granulets are common in cells. Cells split by bianary fission. Several species make cysts under adverse states. Sexual reproduction is absent. Englenoids happen in fresh water and brackish water and very usually in polluted ponds and temporary rain water pools. For e.g.: Euglena, Trachelomonas and Phacus.
Division DINOPHYTA (Dinoflagelles):
Cell wall comprises of cellulose plates that are inside plasma membrane. The number of plates or body scales may be present on cell wall. Cell structure is complex. Majority of forms are unicellular and motile. Several dinoflagellates like Noctiluca, are luminescent. They glow in dark when they are disturbed. Most of the algae contain chlorophyll, a and c and distinctive arotenoid specific to dinoglagellates.
Reserve foods are mostly in form of starch and oil. Asexual method of reproduction is by cell division. Parent cell separates into the number of aplanospores or zoospores or non-motile cells. Sexual reproduction has been lately reported, gametes are smaller than vegetative cells and fusion is isogamous. Formation of cysts with or without pagemtic fusion is also created.
Dinoflagellates are mainly discovered as marine phytoplankton, at times as retide' blooms. Several happen as symbionts in marine animals such as corals (zooxanthellae).
For e.g.: Noctiluca, Gonyaulax, Peridinium and Ceratium.
Division CRYPHOPHYTA (Crytomonads):
Unicellular motile organisms, when alive they are brown in color. Many genera are animal like in morphology and method of nutrition; few are colorless and saprophytic in nature. Cells are with no cell wall ovoid and dorsiventrally flattened. Two flagella are apical and uneven in length. Chloroplasts may be single or numerous in a cell. In some crytomonads there are two, large parietal chloroplasts, or several disc like ones. Pigments comprise chlorophyll a, c, phycocyanin, phycoerythrin and diverse carotenoids.
Reserve photosynthate is starch.
Reproduction is by longitudinal division of cell. Palmelloid forms might generate zoospores. Sexual reproduction hasn't been reported so far. For e.g.: Crytomonas, Chroomonas.
Division BACILIATIOPHYTA (diatoms):
Mainly unicellular forms, few are colonial and filamentous in structure. Cell wall is silicified, comprising of 2 perforated overlapping plates. It is extremely ornamented on surface. Chromatophores are brownish in color because of large amounts of carotenoids. Photosynthetic pigments are chlorophyll a and c, diatoxanthin, fucoxanthin, diatinoxanthin and diatoxanthin.
General storage product is oil and chrysolaminarin. Reproduction happens by vegetative and sexual methods. Diatom cells unlike other algae are diploid in nature. Sexual fusion is homothallic, inside individuals of same clone. Two amoeboid gametes fuse to make zygote that develops into auxospore. Fusion may be oogamous, isogamous, or anisogamous type.
Diatoms are extensively dispersed in fresh water and sea as planktons, on mud surface, moist rocks and sand. They may even be epizoid, epiphytic or endozoid. Vast deposits of fossil diatom shells known as diatomaceous earth are mined and utilized in different industries. For e.g.: Navicula, Coscinodiscus, Diatoma and Fragilaria. At end we would like to indicate that categorization of algae is uncertain and can be enhanced by employing new and enhanced techniques such as DNA fingerprinting etc. that can explain genetic relatedness of organisms.
Orderly Position of Some Genera:
Anacystis:
Family - Chroococcaceae,
Order - Chroococcales,
Division - Cyanophyta
Microcystis:
Nostoc:
Family - Nostoceceae,
Order - Nostocales
Chlamydomonas:
Family - Chlamydomonadaceae
Order - Volvocales
Division - Chlorophyta.
Volvox:
Division - Chlorophyta
Ulothrix:
Family - Ulotrichaceae,
Order - Ulotrichales,
Ulva:
Family - Ulvaceae
Oedogoium:
Family - Oedogoniaceae,
Order - Oedogoniales,
Coleochaete:
Family - Coleochaetaceae,
Order - Chaetophorales
Drapanaldiopsis
Family - Chaetophoraceae,
Ectocarpus:
Family - Ectocarpaceae,
Order - Ectocarpales,
Division - Phaeophyta.
Fucus:
Family - Fuscaceae,
Order - Fucales,
Laminaria:
Family - Laminariaceae,
Order - Laginariales,
Polysiphonia:
Family - Rhodomelaceae,
Order - Ceramiales,
Division - Rhodophyta.
Tutorsglobe: A way to secure high grade in your curriculum (Online Tutoring)
Expand your confidence, grow study skills and improve your grades.
Since 2009, Tutorsglobe has proactively helped millions of students to get better grades in school, college or university and score well in competitive tests with live, one-on-one online tutoring.
Using an advanced developed tutoring system providing little or no wait time, the students are connected on-demand with a tutor at www.tutorsglobe.com. Students work one-on-one, in real-time with a tutor, communicating and studying using a virtual whiteboard technology. Scientific and mathematical notation, symbols, geometric figures, graphing and freehand drawing can be rendered quickly and easily in the advanced whiteboard.
Free to know our price and packages for online biology tutoring. Chat with us or submit request at [email protected]
Mechanism of Genetic Variation and Hereditary tutorial all along with the key concepts of Genetic Variation, Mutation, Spontaneous Mutation, Induced Mutation, Types of Mutation, Genetic Recombination and Mechanism of Recombination
Energy Metabolism tutorial all along with the key concepts of Enzymes and Energy, Regulating Metabolism, Do Enzymes Regulate Metabolic, Energy Transformations in Plants Photosynthesis and Flow of Energy
tutorsglobe.com flower is a modified stem evidence assignment help-homework help by online flower-a metamorphosed shoot tutors
tutorsglobe.com antigen antibody reactions assignment help-homework help by online immunology tutors
Probability tutorial all along with the key concepts of General Principles of probability, First Law of Probability, Genetic Considerations and Second Law of Probability
General ledger is the support of any accounting system that holds financial and non-financial data for an organization.
magnetism of materials tutorial all along with the key concepts of response of different substances to a magnetic field, magnetic moment and angular momentum, diamagnetism and paramagnetism and larmor precession
tutorsglobe.com anaerobic respiration assignment help-homework help by online respiration tutors
Categories and Nomenclature of Soil Taxonomy tutorial all along with the key concepts of Soil Orders, Alfisols, Andisols, Entisols, Gelisols, Inceptisols, Histosols, Vertisols, Mollisols, Ultisols and Oxisols
tutorsglobe.com thalamus assignment help-homework help by online the brain tutors
Theory and lecture notes of Fiscal Policy-Automatic Stabilizers all along with the key concepts of Rules vs. Authorities, Competence and Objectives, Political Business Cycle , Central Bank Independence. Tutorsglobe offers homework help, assignment help and tutor’s assistance on Fiscal Policy-Automatic Stabilizers.
Synthesis and Reactions of Benzofuran and Benzothiophene tutorial all along with the key concepts of Physical and Chemical Properties, Synthesis of Benzofuran and Benzothiophenes
tutorsglobe.com mycoplasma assignment help-homework help by online medical bacteriology tutors
tutorsglobe.com ramsay-raleighs method assignment help-homework help by online isolation of noble gases tutors
General Embryology tutorial all along with the key concepts of Gametogenesis, Kinds of Egg Membranes, Fertilization, Mechanism of Fertilization, Cleavage, Kinds of Cleavage, Planes of Cleavage, Patterns of Cleavage, Blastulation, Gastrulation and Organogenesis
1952402
Questions Asked
3689
Tutors
1458379
Questions Answered
Start Excelling in your courses, Ask an Expert and get answers for your homework and assignments!!