Name: stramenopile algae: diatoms, golden, brown
Uploaded: 2025-06-12T06:31:27.000Z
Duration: 1 min 19 s
Channel: JoVE

Diatomlar, altın algler ve kahverengi algler, filogenetik olarak Stramenopileler olarak sınıflandırılan başka bir alg grubunu oluşturur. Diatomlar, deniz ve tatlı su ortamlarında bulunan tek hücreli ve fotosentetik organizmalardır. Proteinler ve polisakkaritler içeren silika bazlı bir hücre duvarı olan frustule adı verilen koruyucu bir yapıya sahiptirler. Frustüller ayrıca iğneli veya radyal olarak simetrik desenler sergileyen çeşitli karmaşık şekiller oluşturur. Altın algler veya krizofitler, deniz ve tatlı su ortamlarında bulunan fototrofik organizmalardır. Ochromonas gibi bazı türler tek hücreliyken, Dinobryon türleri koloniler oluşturur. Altın renkleri kloroplast pigmenti fukoksantinden kaynaklanır ve fotosentez için öncelikle klorofil c kullanırlar. Kahverengi algler yalnızca denizel ve tamamen çok hücreli türlerdir. Birçok kahverengi alg büyük boyutlara ulaşabilir. Gelgit bölgelerinde yaygın bir deniz yosunu olan fucus 2 metreye kadar büyüyebilirken, Macrocystis gibi dev yosun 50 metreye kadar büyüyebilir.

diğer algler

Other Algae

Stramenopiles grubu baz&#305; fototrof mikroorganizmalar&#305; i&#231;erir. Bu grubun &#252;yeleri, &#231;ok say&#305;da k&#305;sa, k&#305;l benzeri uzant&#305;larla kapl&#305; flagellalara sahiptir; bu &#246;zellik, grubun ad&#305;n&#305;n k&#246;kenini olu&#351;turan Latince "saman" ve "k&#305;l" kelimelerinden esinlenilmesine neden olmu&#351;tur. Stramenopiles&#8217;in ba&#351;l&#305;ca kategorileri aras&#305;nda diyatomlar, alt&#305;n algler ve kahverengi algler yer al&#305;r.
Diyatomlar, fotosentetik, tek h&#252;creli &#246;karyotlard&#305;r ve 200'den fazla bilinen cinse sahiptir. Hem denizel hem de tatl&#305; su ortamlar&#305;ndaki planktonik topluluklarda kilit rol oynarlar. Diyatomlar&#305;n ay&#305;rt edici &#246;zelli&#287;i, proteinler ve polisakkaritlerle g&#252;&#231;lendirilmi&#351; silika (silikon dioksit) esasl&#305; h&#252;cre duvar&#305;na sahip olmalar&#305;d&#305;r. Fr&#252;st&#252;l olarak adland&#305;r&#305;lan bu koruyucu yap&#305;, avc&#305;lara kar&#351;&#305; koruma sa&#287;lar ve h&#252;cre bozunduktan sonra bile uzun s&#252;re sa&#287;lam kalabilir. Diyatom fr&#252;st&#252;lleri &#231;e&#351;itli karma&#351;&#305;k &#351;ekillerde bulunur ve s&#305;kl&#305;kla simetrik desenler sergiler. Baz&#305; t&#252;rler &#231;ift yanl&#305; (pinnat) simetri, baz&#305;lar&#305; ise radyal simetri g&#246;sterir. Silika i&#231;erikleri nedeniyle bu yap&#305;lar, tortul tabakalarda milyonlarca y&#305;l boyunca bozulmadan kalabilir. Bu nedenle, diyatom fosilleri, eski tek h&#252;creli &#246;karyotlara ait en iyi korunmu&#351; &#246;rnekler aras&#305;ndad&#305;r ve yakla&#351;&#305;k 200 milyon y&#305;l &#246;nce ortaya &#231;&#305;kt&#305;klar&#305;na dair kan&#305;tlar bulunmaktad&#305;r.
Alt&#305;n algler ve kahverengi algler, Stramenopiles&#8217;in di&#287;er b&#252;y&#252;k dallar&#305;n&#305; temsil eder. Alt&#305;n algler veya krizofitler, ba&#351;l&#305;ca denizel ve tatl&#305; su ortamlar&#305;nda bulunur ve burada fototrof olarak i&#351;lev g&#246;r&#252;rler. Baz&#305; t&#252;rler, fagositoz yoluyla organik maddeyi t&#252;ketebilir ya da &#231;&#246;z&#252;nm&#252;&#351; bile&#351;ikleri absorbe edebilir. Alt&#305;n alglerin &#231;o&#287;u tek h&#252;creli ve hareketliyken, Dinobryon gibi baz&#305;lar&#305; koloni olu&#351;turur. Alt&#305;n-kahverengi renkleri, karotenoid pigment olan fukoksantin varl&#305;&#287;&#305;ndan kaynaklan&#305;r. Bir&#231;ok di&#287;er fotosentetik organizmada bulunan klorofil a yerine, alt&#305;n algler a&#287;&#305;rl&#305;kl&#305; olarak klorofil c kullan&#305;r ve k&#305;rm&#305;z&#305; alglere &#246;zg&#252; fikobiliproteinleri i&#231;ermez. Bu gruba ait iyi &#231;al&#305;&#351;&#305;lm&#305;&#351; bir &#246;rnek, her h&#252;cresinde bir ya da iki kloroplast bulunan tek h&#252;creli t&#252;r Ochromonas&#8217;t&#305;r.
Buna kar&#351;&#305;l&#305;k, kahverengi algler yaln&#305;zca denizel ortamlarda bulunur ve tamamen &#231;ok h&#252;crelidir; bilinen hi&#231;bir tek h&#252;creli temsilcileri yoktur. Kahverengi alglerin &#231;o&#287;u makroskopiktir ve baz&#305; t&#252;rler dikkate de&#287;er b&#252;y&#252;kl&#252;klere ula&#351;abilir. Macrocystis gibi dev yosunlar 50 metreye kadar uzayabilirken, gelgit b&#246;lgelerinde yayg&#305;n olarak bulunan Fucus 2 metreye kadar b&#252;y&#252;yebilir. Bu alglerin kahverengi ya da ye&#351;ilimsi kahverengi rengi, h&#252;crelerindeki fukoksantin yo&#287;unlu&#287;una ba&#287;l&#305;d&#305;r. Kahverengi algler, denizel makroyosunlar aras&#305;nda en bol bulunanlar aras&#305;ndad&#305;r ve baz&#305; k&#305;y&#305; b&#246;lgelerinde, a&#351;&#305;r&#305; b&#252;y&#252;meleri sonucu b&#252;y&#252;k miktarlarda k&#305;y&#305;ya vurmalar&#305; ve bozunmalar&#305;, ho&#351; olmayan kokulara yol a&#231;arak sorunlara neden olabilir.

Diğer Algler

Stramenopiles grubu baz&#305; fototrof mikroorganizmalar&#305; i&#231;erir. Bu grubun &#252;yeleri, &#231;ok say&#305;da k&#305;sa, k&#305;l benzeri ...

Education

JoVE Core

Microbiology

Mikrobiyoloji

Unit

Birim

Microbial Diversity

Mikrobiyal Çeşitlilik

KEY TERMS AND CONCEPTS

TEMEL TERİMLER VE KAVRAMLAR

stramenopile algae: diatoms, golden, brown

Stramenopile algae include diatoms, golden algae, and brown algae. These phototrophic microorganisms have flagella with many short, hairlike extensions. That feature gave the group its name, which comes from Latin words meaning “straw” and “hair.”

Diatoms are unicellular, photosynthetic eukaryotes, and more than 200 genera are known. They are important parts of plankton in both marine and freshwater ecosystems. Their most distinctive feature is a silica-based cell wall called a frustule. This wall is reinforced with proteins and polysaccharides and helps protect the cell from predators. Frustules also stay intact after the cell dies, and their intricate shapes often show pinnate or radial symmetry. Because they are made of silica, they can persist in sediment for millions of years. Diatom fossils are among the best-preserved fossils of ancient unicellular eukaryotes, and the group likely appeared about 200 million years ago.

Golden algae, also called chrysophytes, live mainly in marine and freshwater environments. They are phototrophs, but some species can also take in organic material by phagocytosis or by absorbing dissolved compounds. Most golden algae are unicellular and motile, although some, such as Dinobryon, form colonies. Their golden-brown color comes from the pigment fucoxanthin. They use chlorophyll c rather than chlorophyll a, and they lack the phycobiliproteins found in red algae. Ochromonas is a well-studied unicellular example, and it usually has one or two chloroplasts per cell.

Brown algae are different from the other groups because they are exclusively marine and multicellular. No unicellular brown algae are known. Many are large enough to see easily, and some grow to impressive sizes. Giant kelp, such as Macrocystis, can reach up to 50 meters in length, while Fucus, a common intertidal seaweed, can grow up to 2 meters. Their brown or greenish-brown color depends on how much fucoxanthin is present in the cells. Brown algae are among the most common marine seaweeds, and in some coastal areas, large amounts wash ashore and decompose, creating a bad smell.

Stramenopile Algae: Diatoms, Golden, Brown

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bacterial phylum cyanobacteria

Cyanobacteria and Oxygenic Photosynthesis

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bacterial phylum actinobacteria

Actinobacteria: Soil Bacteria and Cheese

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Firmicutes: Bacteria, Fermentation, and Spores

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hyperthermophilic bacteria

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other unique bacteria

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Zygomycota: Spores, Hyphae, and Roles

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fungal phylum microsporidia

Microsporidia Spores and Host Infection

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fungal phylum ascomycota

Ascomycota: Sac Fungi and Their Spore Cycle

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fungal phylum basidiomycota

Basidiomycota: Mushrooms, Spores, and Ecological Roles

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overview of algae

Algae Structure, Habitats, and Reproduction

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red algae

Red Algae Pigments, Shapes, and Uses

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green algae

Green Algae: Forms, Habitats, and Roles

Green algae are photosynthetic organisms with chlorophylls a and b in their chloroplasts. These pigments give them a green color. They differ from red algae because they lack phycobiliproteins, the pigments that produce red or blue-green tones in red algae. In pigment makeup, green algae are close to plants, and they share a close evolutionary relationship with them. Green algae belong to Phylum Chlorophyta in the Kingdom Archaeplastida. They are usually divided into two main groups:...

other algae

Stramenopile algae include diatoms, golden algae, and brown algae. These phototrophic microorganisms have flagella with many short, hairlike extensions. That feature gave the group its name, which comes from Latin words meaning “straw” and “hair.” Diatoms are unicellular, photosynthetic eukaryotes, and more than 200 genera are known. They are important parts of plankton in both marine and freshwater ecosystems. Their most distinctive feature is a silica-based cell wall called a frustule. This...

overview of protists

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diversity of protists i

Excavata Protists and Their Adaptations

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diversity of protists ii

Alveolates: Ciliates, Dinoflagellates, Apicomplexans

Alveolates are protists with tiny sacs called alveoli beneath the cell membrane. These sacs may help control water balance by limiting how much water moves in and out of the cell. In dinoflagellates, alveoli may also act like armor plates. The three main alveolate groups are ciliates, dinoflagellates, and apicomplexans. Ciliates move with cilia, which are short hair-like structures that can cover the whole cell or appear in rows or tufts. One well-known ciliate is Paramecium, which uses cilia...

diversity of protists iii

Rhizaria: Pseudopods, Tests, and Skeletons

Rhizaria are unicellular protists with threadlike pseudopodia, which are thin cytoplasmic extensions used for movement and feeding. Their amoeboid shape once caused taxonomic confusion, but molecular phylogenetics has since shown where they fit on the evolutionary tree. This group includes Chlorarachniophyta, Radiolaria, and Foraminifera, and each lineage has adapted to a different ecological niche and metabolic strategy. Chlorarachniophyta are unicellular phototrophic protists found in marine...

diversity of protists iv

Amoebozoa: Movement and Life Cycles

Amoebozoa are a diverse group of terrestrial and aquatic protists. They move and feed with lobe-shaped pseudopodia. This feature sets them apart from Rhizaria, which have threadlike pseudopodia. The group includes gymnamoebas, entamoebas, and the plasmodial and cellular slime molds. Phylogenetic evidence also shows that Amoebozoa split from a lineage that later gave rise to fungi and animals. Gymnamoebas are free-living protists that live in water and soil. They move by amoeboid movement,...

key terms and concepts

Learn how diatoms, golden algae, and brown algae differ in structure, pigments, habitats, and size, from silica frustules to giant kelp.

Stramenopile Algae: Diatoms, Golden, Brown | JoVE K12

JoVE Core Microbiology provides an engaging introduction to the microbial world and its influence on health, industry, and the environment. This comprehensive collection covers key concepts such as microbial structure, metabolism, genetics, and ecology. It introduces essential laboratory techniques and microscopy methods through visually engaging animations. Corresponding scientist-in-action videos bridge classroom concepts with real-world research and applications.

microbiology

Stramenopile Algae: Diatoms, Golden, Brown

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