Algae Algae Algae are the chlorophyllus thallophytes that

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Algae

Algae

Algae • Algae are the chlorophyllus thallophytes that can manufacture their own food and

Algae • Algae are the chlorophyllus thallophytes that can manufacture their own food and they produce oxygen during photosynthesis. So they are called as autotrophic thallophytes. • The term thallus is used for plant body that is not differentiated into root, stem and leaves. Lacks vascular system. • “The study of algae is known as phycology. ”

Habit and habitat • The algae re predominantly aquaticand are found both in fresh

Habit and habitat • The algae re predominantly aquaticand are found both in fresh and salt-water habitats. • According to the habitat the algae can be classifiedas: v Aquatic algae v Terrestrial v Aerophytes v Cryophytes v Thermophytes

Algae Classification • There is three main Algae classification: • Chlorophyceae – These are

Algae Classification • There is three main Algae classification: • Chlorophyceae – These are called green algae, due to the presence of pigments chlorophyll a and b. Examples are Chlamydomonas, Spirogyra, and Chara • Phaeophyceae – Also called as brown algae, they are predominantly marine. They have chlorophyll a, c, carotenoids and xanthophyll pigments. Examples are Dictyota, Laminaria, and Sargassum • Rhodophyceae – They are the red algae because of the presence of the red pigment, r-phycoerythrin. Examples are Porphyra, Gracilaria, and Gelidium.

Unicellular motile • Chlamydomonas • Occurance It is fresh water free swiming alga. It

Unicellular motile • Chlamydomonas • Occurance It is fresh water free swiming alga. It is frequenlty found in standing water, ponds, ditches, pools, rain water and in damp soil. Structure of Chlamydomonas: Chlamydomonas is unicellular, motile green algae. The thallus is represented by a single cell. The shape of thallus can be oval, spherical, oblong, ellipsoidal or pyriform. The pyriform or pear shaped thalli are common, they have narrow anterior end a broad posterior end

The structure of thallus can be divided into following parts: Cell Wall Cytoplasm Flagella

The structure of thallus can be divided into following parts: Cell Wall Cytoplasm Flagella Neuro-motor Apparatus • Chloroplast • Stigma or Eyespot • •

Chlamydomonas reproduces both asexually and sexually • Asexual reproduction occurs by zoospores, aplanospores, hypnospores,

Chlamydomonas reproduces both asexually and sexually • Asexual reproduction occurs by zoospores, aplanospores, hypnospores, or a palmella stage • Sexual reproduction is through isogamy, anisogamy or oogamy

Asexual reproduction

Asexual reproduction

Asexual reproduction

Asexual reproduction

Sexual reproduction

Sexual reproduction

Anisogaymous reproduction

Anisogaymous reproduction

Oogamous reproduction

Oogamous reproduction

Life cycle of chlymadomonas

Life cycle of chlymadomonas

Graphic life cycle

Graphic life cycle

Economic Importance • 1. Food: A number of green algae are used as food,

Economic Importance • 1. Food: A number of green algae are used as food, e. g. , Ulva, Caulerpa, Enteromorpha. Chlorella can yield food rich in lipids, proteins, vitamins and minerals. • 2. Antibiotics: They can be extracted from Chlorella and Caulerpa. • 3. Parasites: Cephaleuros virescens causes red rust of tea and reduces yield of tea. It also reduces the yield of coffee, pepper, citrus, etc. • 4. Sewage Oxidation: Sewage oxidation ponds contain a number of green algae, e. g. , Chlamydomonas, Chlorella, Scenedesmus.

 • • • https: //www. toppr. com/guides/biology/plant-kingdom/algae/ https: //www. biologydiscussion. com/algae/life-cycle-algae/chlamydomonasposition-occurrence-and-structure-with-diagrams/21052 https: //www.

• • • https: //www. toppr. com/guides/biology/plant-kingdom/algae/ https: //www. biologydiscussion. com/algae/life-cycle-algae/chlamydomonasposition-occurrence-and-structure-with-diagrams/21052 https: //www. google. com/search? q=structure+of+chlamydomonas&rlz=1 C 1 CHBD_ en. PK 817&source=lnms&tbm=isch&sa=X&ved=2 ah. UKEwjpw 5 z. G 0 Ovr. Ah. WUi Fw. KHRf. MB 0 EQ_AUo. AXo. ECA 4 QAw&biw=1366&bih=657#imgrc=Q 3 MO_bgas 2 p. H_ M https: //www. biologydiscussion. com/algae/life-cycle-of-chlamydomonas-withdiagram/53699 https: //www. biologydiscussion. com/algae/green-algae-characters-and-economicimportance-withdiagram/52153#: ~: text=A%20 number%20 of%20 green%20 algae, %2 C%20 proteins %2 C%20 vitamins%20 and%20 minerals.