Podcast
Questions and Answers
What kingdom are blue-green algae classified under?
What kingdom are blue-green algae classified under?
Which of the following structures is absent in blue-green algae?
Which of the following structures is absent in blue-green algae?
Which pigments are found in blue-green algae?
Which pigments are found in blue-green algae?
What is the primary mode of reproduction in blue-green algae?
What is the primary mode of reproduction in blue-green algae?
Signup and view all the answers
What type of cell wall composition is characteristic of blue-green algae?
What type of cell wall composition is characteristic of blue-green algae?
Signup and view all the answers
What carbohydrate do blue-green algae produce during photosynthesis?
What carbohydrate do blue-green algae produce during photosynthesis?
Signup and view all the answers
What is a unique feature of some filamentous forms of blue-green algae?
What is a unique feature of some filamentous forms of blue-green algae?
Signup and view all the answers
Which blue-green alga is known to impart a reddish color to water?
Which blue-green alga is known to impart a reddish color to water?
Signup and view all the answers
Where can blue-green algae typically grow?
Where can blue-green algae typically grow?
Signup and view all the answers
What type of reproduction do blue-green algae primarily use?
What type of reproduction do blue-green algae primarily use?
Signup and view all the answers
What ecological role do some blue-green algae play in relation to fish?
What ecological role do some blue-green algae play in relation to fish?
Signup and view all the answers
Which genus of blue-green algae is known for growing in filaments?
Which genus of blue-green algae is known for growing in filaments?
Signup and view all the answers
What term describes the shorter pieces produced during the reproduction of Oscillatoria?
What term describes the shorter pieces produced during the reproduction of Oscillatoria?
Signup and view all the answers
What significant feature distinguishes blue-green algae such as Nostoc in terms of their biological classification?
What significant feature distinguishes blue-green algae such as Nostoc in terms of their biological classification?
Signup and view all the answers
Which conditions may lead to the death of cattle in relation to blue-green algae?
Which conditions may lead to the death of cattle in relation to blue-green algae?
Signup and view all the answers
Why might the classification of blue-green algae be considered complex and variable?
Why might the classification of blue-green algae be considered complex and variable?
Signup and view all the answers
What is the function of heterocysts in Nostoc filaments?
What is the function of heterocysts in Nostoc filaments?
Signup and view all the answers
Which pigment is NOT found in Nostoc cells?
Which pigment is NOT found in Nostoc cells?
Signup and view all the answers
What is the protective outer layer of Nostoc filaments called?
What is the protective outer layer of Nostoc filaments called?
Signup and view all the answers
How do Nostoc colonies typically reproduce?
How do Nostoc colonies typically reproduce?
Signup and view all the answers
What role do Nostoc and Anabaena play in rice paddies?
What role do Nostoc and Anabaena play in rice paddies?
Signup and view all the answers
Which structural characteristic defines Nostoc filaments?
Which structural characteristic defines Nostoc filaments?
Signup and view all the answers
What is the main component of the thick cell wall in Nostoc cells?
What is the main component of the thick cell wall in Nostoc cells?
Signup and view all the answers
Which describes the typical appearance of Nostoc colonies?
Which describes the typical appearance of Nostoc colonies?
Signup and view all the answers
What is the mechanism of asexual reproduction in Nostoc?
What is the mechanism of asexual reproduction in Nostoc?
Signup and view all the answers
What ecological role do Nostoc play in agriculture?
What ecological role do Nostoc play in agriculture?
Signup and view all the answers
What significant compound has N.muscorum been shown to accumulate?
What significant compound has N.muscorum been shown to accumulate?
Signup and view all the answers
What is a characteristic feature of Oscillatoria?
What is a characteristic feature of Oscillatoria?
Signup and view all the answers
How do Nostoc species respond to unfavorable environmental conditions?
How do Nostoc species respond to unfavorable environmental conditions?
Signup and view all the answers
What do the filaments of Oscillatoria primarily consist of?
What do the filaments of Oscillatoria primarily consist of?
Signup and view all the answers
What industrial application might stem from the properties of N.muscorum?
What industrial application might stem from the properties of N.muscorum?
Signup and view all the answers
Which of the following describes the photosynthetic structures found in the chromoplast of Oscillatoria?
Which of the following describes the photosynthetic structures found in the chromoplast of Oscillatoria?
Signup and view all the answers
Study Notes
Blue-green Algae
- Algae are not a related group, various forms are in different kingdoms
- Lack nuclei, so are prokaryotic and placed in kingdom Monera (cyanobacteria)
- Euglenophyta, Chrysophyta, and Pyrrophyta are placed in kingdom Protista (not multicellular)
- Lack membrane-bound organelles like nuclei, mitochondria, Golgi bodies, and plastids
- Cell walls composed of layers of mucoprotein, polysaccharides (including lipopolysaccharides), and lack cellulose
- Pigments include chlorophyll a, carotenoids, phycocyanin (blue), and phycoerythrin
- Morphology ranges from unicellular to filamentous, often with mucilaginous sheaths
- Some can fix atmospheric nitrogen
- Asexual reproduction is common (binary fission, multiple fission, endospores, hormogonia)
- Trichodesmium erythraeum imparts a reddish-blue color to water (e.g., the Red Sea)
- Chlorophyll a is responsible for photosynthesis, producing glycogen
- Cytoplasm is around the perimeter, with chromatin in the incipient nucleus
- No vacuoles in healthy young cells
- Thrive in diverse conditions (snow, ice, hot springs, desert soils)
Nostoc
- Genus of blue-green algae (cyanobacteria)
- Found in freshwater, on rocks/bottoms of lakes, on tree trunks, and in bryophytes (e.g. Azolla, Anthoceros)
- Form colonies as large as a plum
- Colonies are embedded in a jelly-like matrix; can float in water
- Important nitrogen-fixing bacteria, aiding rice paddy fertility
- Filamentous, unbranched, gelatinous colonies
- Consist of chains of cells (trichomes)
- Some cells are specialized heterocysts for nitrogen fixation
- Covered by a mucilaginous sheath for absorbing and retaining water, made of polysaccharides and proteins
Oscillatoria
- Common blue-green alga in filaments (lakes, ponds, moist soil)
- Filaments formed by transverse cell division
- Cells are essentially similar in size
- Capable of undulating movement ("oscillatory movement")
- Reproduction by fragmentation (hormogonia)
- Approximately 30 species in North America
- May impart a putrescent odor to water
General Characteristics of Blue-Green Algae
- Colonies vary in shape, size, and color (greenish, bluish-green, red-brown, yellow-green)
- Have extracellular pigments (e.g., nostocine, scytonemin) to protect from UV radiation
- Cell walls made of peptidoglycan
- Cytoplasm differentiated into outer (colored) chromoplast and inner clear cytoplasm
- Contain various pigments including chlorophyll (green), phycocyanin (blue), and phycoerythrin (red)
- DNA is present but without histones
- Vegetative reproduction by fragmentation or spore formation (hormogonia)
- Important in paddy fields, increasing soil nutrient value, a delicacy in some Asian countries
- Can accumulate polyhydroxy butyrate (precursor for plastic)
- Some species show antibacterial/antiviral activity
Additional Notes
- Reproduction (Asexual): akinetes (resting spores), heterocysts (nitrogen fixation), hormogonia (short segments of trichome), fragmentation
- Reserve food material: cyanophycean starch, lipids, cyanophycin
- Many species exist, potentially as many as 7500 species.
- Various applications ranging from bioremediation and production of hydrogen to potential drug development (antibacterial and antiviral activity)
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz provides an overview of blue-green algae, also known as cyanobacteria, including their classification, structure, and pigmentation. Explore their unique characteristics such as their prokaryotic nature, lack of organelles, and reproduction methods. Test your knowledge on their ecological importance and diverse morphology.
