Phylum Bacillariophyta, Xanthophyta & Chrysophyta
•Transferir como PPTX, PDF•
16 gostaram•8,537 visualizações
Bacillariophyta is a phylum of the kingdom Protista, consisting of mostly unicellular aquatic algae commonly referred to as Diatoms. Xanthophytes are the yellow-green algae whereas Chrysophytes are the golden-brown algae.
Recomendados
Mais conteúdo relacionado
Mais procurados
Mais procurados (20)
Semelhante a Phylum Bacillariophyta, Xanthophyta & Chrysophyta
Semelhante a Phylum Bacillariophyta, Xanthophyta & Chrysophyta (20)
Mais de Fasama H. Kollie
Mais de Fasama H. Kollie (20)
Último
Último (20)
Phylum Bacillariophyta, Xanthophyta & Chrysophyta
- 1. Phylum Bacillariophyta Diatoms Presented by: Fasama Hilton Kollie Lecturer, Department of Biology Mother Patern College of Health Sciences February 28, 2019
- 2. Lesson Outline • Overview of the phylum Bacillariophyta, Xanthophyta and Chrysophyta • General characteristics of diatoms, yellow-green algae and golden brown algae
- 3. Lesson Objectives • Upon completion of this topic, students will be able to; 1. Describe diatoms, xanthophytes and chrysophytes 2. Identify the similarities and difference among chromist
- 4. Phylum Bacillariophyta: Diatoms • Bacillariophyta is a phylum of the kingdom Protista, consisting of mostly unicellular aquatic algae • Diatoms • Diatoms are a major group of microalgae, and are among the most common types of phytoplankton • About 5,600 extant species
- 5. General Characteristics • Diatoms occur in fresh water, salt water and in moist vegetation on land • Some species are attached to substracts, others are free swimming • Most live pelagically in open water, although some live as surface films at the water-sediment interface (benthic)
- 6. General Characteristics Cont’d… • Diatoms generally are formed in two general shapes • Centric diatoms • Pennate diatoms Pennate Centric
- 7. General Characteristics Cont’d… • Cells are surrounded by a rigid two part box like cell wall composed of silica, called frustule • It’s elaborate, with ornamental patterns and numerous tiny pores, Composed of silica (silicon dioxide, SiO2) • Reproduce asexually
- 9. Phylum Xanthophyta: Yellow-Green Algae • Division of algae commonly known as yellow-green algae • Consist of appx. 600 species of algae most of which inhabit fresh water • They vary in form and size from single- celled organisms to small filamentous forms or simple colonies Colonia form Filamentous form
- 10. General Characteristics • Mostly found in fresh water some in marine environment or damp soil • They consist of both free living and solitary organisms
- 11. General Characteristics Cont’d… • Chlorophyll a and c • Xanthophyll (dominant pigments) • Unicellular • Some species also exist as colonies or as long filaments of cells • Other are Coenocytic • Consisting of a single cytoplasmic mass that contains many nucleiColonia form Filamentous form
- 12. Coenocytic:
- 13. General Characteristics Cont’d… • Xanthophyte cell walls consist of Cellulose and Hemicellulose
- 14. General Characteristics Cont’d… • Most have two flagella arising from opposite ends of the cell • Motile cells with a forwardly directed tinsel flagellum and a posteriorly directed whiplash flagellum • Some species of xanthophytes serve as a model system for investigating chloroplast movement
- 15. Reproduction In Yellow-Green Algae • Reproduction is predominantly asexual which involves fragmentation of filaments or spore formation • Spores may be flagellated and free- swimming (zoospores), or they may be non-flagellated
- 16. Reproduction Cont’d… • Sexual reproduction is known only in two genera: • Botrydium, in which the sex cells are isogamous, and Vaucheria, in which the cells are oogamous Botrydium granulatum Vaucheria
- 18. Phylum Chrysophyta: Golden-Brown Algae • Unicellular organisms assigned to the class Chrysophyceae • Many have characteristics gold color (Greek chrysos, “gold” and phyto, “plant) • Appx. 1,000 species • Mostly freshwater and marine planktonic algae • Free swimming and colonial organisms Synura Fig. 1.0 Dinobryon
- 19. General Characteristics Cont’d… • Chlorophyll a, c and fucoxanthin • There is no common cell structure • Autotrophs • Characterized by the use of oil droplets as a food reserve or Polysaccharide laminarin Synura
- 20. General Characteristics Cont’d… • The formation of a dormant spores in golden-brown algae serve as their hallmark feature • Statospores (statocyst) • These spores are encased in a wall made of silica • It contains Nucleus, Chloroplast, Basal bodies, Golgi apparatus, many Mitochondria and Ribosomes
- 21. Reproduction • Sexual reproduction is rare • Asexual reproduction is common • This is by the formation of motile and nonmotile spores and by cell division
- 22. Reference • Nabors, Murray W., INTRODUCTION TO BOTANY, Copyright 2004 Pearson Education, Inc., publishing as Benjamin Cummings, 1301 Sansome St., San Francisco, CA 94111. www.aw-bc.com • Chrysophyta. The Columbia Encyclopedia, Sixth Edition. 2001. Copyright 2004 Columbia University Press. • Introduction to the Chrysophyta. UCMP-Berkeley
- 23. “ The most valuable thing a teacher can impart to student is not knowledge and understanding but a longing for knowledge and understanding, and an appreciation for intellectual values, whether they be artistic, scientific, or moral. ” → Albert Einstein
Notas do Editor
- Unicellular eukaryotic algae Single cell algae which has a cell wall of silica Diatoms; due to their glass-like appearance [Silicon dioxide] More than 200 genera of living diatoms are known 5,600 species The most abundant single-cell algae Second larges of both multicellular and unicellular algae
- Chlorophyll a, c and carotenoid Substrate: an underlying substance or layer to which a body is attached Diatoms and dinoflagellates are the major constituent of Phytoplankton
- Diatoms are distinguished by the shape of their frustules into two: Centric diatoms Pennate diatoms Frustules [distinctive cell wall] Few (centric diatoms) are radially symmetric, Whereas most (pennate diatoms) are broadly bilaterally symmetric A unique feature of diatom anatomy is that they are surrounded by a cell wall made of silica (hydrated silicon dioxide), called a frustule
- Each frustule is made up of two valves called thecae, that typically overlap one another Both fit together like the top and bottom of a petridish Lacks flagella generally Only male gametes of centric diatoms are capable of movement by means of flagella Some diatoms secrete a gelatinous substance called mucilage It facilitate movement by gliding Movement in diatoms primarily occurs passively as a result of water currents; however, male gametes of centric diatoms have flagella, permitting active movement for seeking female gametes. Similar to plants, diatoms convert light energy to chemical energy by photosynthesis
- Contain chlorophyll a, c and carotenoid As chromist, they lack chlorophylly b and fucoxanthan, thus having a characteristics color of yellow-green CHROMIST: All algae with chlorophyll a and c Dinoflagellates, xanthophyta, Bacillariophyta, chrysophyta, cryptophyta, prymnesiophyta and chlorophyta 600 species 5th largest single cell algae Next to Euglenophytes with 800 species
- The xanthophyceae are distinguished by; Their food reserve (oil), The quantity of β-carotene in their plastids, and Motile cells with unequal flagella
- Xanthophylls yellow pigments that occur widely in nature and form one of two major divisions of the carotenoid group; the other division is formed by the carotenes COENOCYTIC Forms single mass of cell This functions as a single coordinated unit composed of multiple cells linked structurally and functionally
- Cellulose and hemicellulose are two types of polymers that serve as structural components of the plant cell wall. ... In contrast, hemicellulose is made up of several monomers: xylose, galactose, mannose, rhamnose, and arabinose. Cellulose is a long polymer while hemicellulose is comparatively short
- Two flagella [Biflagellated] Both flagella arise from the lateral surface of their body, not anterior Tinsel flagellum (contain hair-like projection, mastigonemes) Forward direction Whiplash flagellum Backward movement In vaucheria, the chloroplast move to the center of the cell in dim lights and to the edges of the cell in bright light. In darknessness, the chloroplasts are uniformly distributed To prevent light-induced damage to cells Food reserve: chrysolaminarin in vesicle
- Spores are formed inside the cell wall and are released when it ruptures Only two general reproduce sexually
- Isogamous Isogamy is a form of sexual reproduction that involves gametes of similar morphology (similar shape and size), differing in general only in allele expression in one or more mating-type regions. Because both gametes look alike, they cannot be classified as "male" or "female“s Oogamous relating to or denoting reproduction by the union of mobile male and immobile female gametes.
- Microscopic chromists in fresh water 33 genera and 1,000 species Eg: Dinobryon: a colony f single cells living in tubes. Each cell can consume 36 bacteria/hour Some species are colorless, but the vast majority are photosynthetic. As such, they are particularly important in lakes, where they may be the primary source of food for zooplankton. Major consumer of bacteria in cooler lakes
- They possess two unequal length of flagella that emerge perpendicular to each other (biflagellate) Cells usually have one large chloroplast Biflagellate The molecule laminarin is a storage glucan found in brown algae. It is used as a carbohydrate food reserve in the same way that chrysolaminarin is used by phytoplankton, especially in diatoms. Reserve food: Polysaccharide laminarin
- Statospores (statocyst) resting spore especially : a thick-walled resistant spore formed within the cell wall of chrysophytes