biol 227 Exam- Algae |Questions with
Complete Solutions
What are Stromatolites? - ANS *Rock formations that could not be formed by non-biotic
process.
*Present day stomatolites contain cyanobacteria
What is the problem with cyanobacteria? - ANS *Some cyanobacteria produce toxins
-But not always or in all conditions
-Detrimental effect occur when cyanos in large numbers -blooms
Is Cyanobacteria prokaryotic or eukarytoic? - ANS *Cyanobacteria is prokaryotic
*Membrane system (photosynthetic membranes)
What pigments does Cyanobactera use for photosynthesis? - ANS *Chlorophyll a - all
*Chlorophyll b - specific group
*Chlorophyll c- specific group
*Chlorophyll d - specific group (new discovery)
*Carotenoids
*Xanthophylls
*Phycobiliproteins
What is Caroteniods and Xanthophylls? - ANS Carotenoids are organic pigments that are found in
the chloroplasts and chromoplasts of plants and some other photosynthetic organisms,
,including some bacteria and some fungi. Carotenoids can be produced from fats and other
basic organic metabolic building blocks by all these organisms.
Xanthophylls are yellow pigments that form one of two major divisions of the carotenoid group.
Made from B-catotene that plays a vital role in the photosynthetic reaction centre where it
provides a mechanism for photoprotection against auto-oxidation. They also participate in
the energy-transfer process.
What are Phycobiliproteins? - ANS *Phycobiliproteins- proteins + bilin
-Bilins- linear tetrapyroles
-Proteins
2 subunits- alpha and beta each with a bilin or more attached
Examples:
Phycoerythrin - red pigment
Phycocyanin - blue pigment
Allophycocyanin- blue pigment
What are phycobilisomes? - ANS Phycobilisomes are light harvesting antennae of photosystem
II in cyanobacteria, red algae and glaucophytes.
They are found on the photosynthetic membranes. (related to phycobiliproteins)
Each phycobiliprotein has a specific absorption and fluorescence emission maximum in the
visible range of light. Therefore, their presence and the particular arrangement within the
phycobilisomes allow absorption and unidirectional transfer of light energy to chlorophyll a
of the photosystem II.
What is the advantage of proteins+bilin? - ANS *Combination of proteins+bilin give
the pigments a specific absorbance
Examples:
Phycoerythrin - red pigment
Phycocyanin - blue pigment
,Different combination of all the pigments give cyanos different colours
What is the storage system used by Cyanobacteria? - ANS Storage:
*Carbohydrate storage
-Glycogen (alpha-1-4-linked glucan)
*Cyanophycin particles (arginine+aparagine storage)
*Polyphosphate bodies (Phosphate storage)
What is the Motility system used by Cyanobacteria? - ANS Motility:
*No flagella, but can glide, and move up and down in water.
-By using Gas vesicles
What is the Cell Wall in Cyanobacteria made from? - ANS Cell Wall:
*Peptidoglycan (like bacteria)
*Can have sheaths (gelatinous matrix)
What is the Habitat of Cyanobacteria? - ANS Habitat:
*Everywhere there is water!
-Freshwater, Marine, Terrestrial, Soil, Symbionts, Extremophiles (hot and cold)
What is the Reproduction system of Cyanobacteria? - ANS Reproduction:
*NO Sex- but can absorb environmental DNA, and have phages.
* Uses Asexual reproduction
-Binary fission -Endospores
-Exospores
, -Filaments can fragment
What is the Taxonomy of Cyanobactera? (Orders) - ANS *Chroococcales- unicellular, single or in
colonies (clumps)
*Pleurocapsales- endosore producing (baeocytes)
*Oscillatoriales- unbranched filaments, with hormogonia
*Nostocales- unbranched filaments, w/ heterocysts, akinetes, false branching-can form large
gelatinous colonies
*Stigonematales- True branching, w/ heterocysts, akinetes
What is the characteristics of Chroococcales? - ANS The order is characterized by single,
floating cells or colonies which are embedded to a matrix. There is also a lack of differentiation
between apical and basal structures.
What is the characteristics of Nostocales? - ANS It includes filamentous forms, both simple or
branched, and both those occurring as single strands or multiple strands within a sheath.
Some but not all members show a decrease in width from the base. Again, some but not all
have heterocysts.
--Can form large gelatinous colonies
What is the characteristics of Stigonematales? - ANS Includes filamentous strains that
produce hormogonia and exhibit true branching.
What is the system of Hormogonia in cyanobacteria? - ANS Hormogonia is:
*Method of vegetative propagation
*Programmed cell death
What is Heterocysts in cyanobacteria? - ANS *Heterocysts- cells with thick walls and no PSII
*Site of nitrogen fixation
Complete Solutions
What are Stromatolites? - ANS *Rock formations that could not be formed by non-biotic
process.
*Present day stomatolites contain cyanobacteria
What is the problem with cyanobacteria? - ANS *Some cyanobacteria produce toxins
-But not always or in all conditions
-Detrimental effect occur when cyanos in large numbers -blooms
Is Cyanobacteria prokaryotic or eukarytoic? - ANS *Cyanobacteria is prokaryotic
*Membrane system (photosynthetic membranes)
What pigments does Cyanobactera use for photosynthesis? - ANS *Chlorophyll a - all
*Chlorophyll b - specific group
*Chlorophyll c- specific group
*Chlorophyll d - specific group (new discovery)
*Carotenoids
*Xanthophylls
*Phycobiliproteins
What is Caroteniods and Xanthophylls? - ANS Carotenoids are organic pigments that are found in
the chloroplasts and chromoplasts of plants and some other photosynthetic organisms,
,including some bacteria and some fungi. Carotenoids can be produced from fats and other
basic organic metabolic building blocks by all these organisms.
Xanthophylls are yellow pigments that form one of two major divisions of the carotenoid group.
Made from B-catotene that plays a vital role in the photosynthetic reaction centre where it
provides a mechanism for photoprotection against auto-oxidation. They also participate in
the energy-transfer process.
What are Phycobiliproteins? - ANS *Phycobiliproteins- proteins + bilin
-Bilins- linear tetrapyroles
-Proteins
2 subunits- alpha and beta each with a bilin or more attached
Examples:
Phycoerythrin - red pigment
Phycocyanin - blue pigment
Allophycocyanin- blue pigment
What are phycobilisomes? - ANS Phycobilisomes are light harvesting antennae of photosystem
II in cyanobacteria, red algae and glaucophytes.
They are found on the photosynthetic membranes. (related to phycobiliproteins)
Each phycobiliprotein has a specific absorption and fluorescence emission maximum in the
visible range of light. Therefore, their presence and the particular arrangement within the
phycobilisomes allow absorption and unidirectional transfer of light energy to chlorophyll a
of the photosystem II.
What is the advantage of proteins+bilin? - ANS *Combination of proteins+bilin give
the pigments a specific absorbance
Examples:
Phycoerythrin - red pigment
Phycocyanin - blue pigment
,Different combination of all the pigments give cyanos different colours
What is the storage system used by Cyanobacteria? - ANS Storage:
*Carbohydrate storage
-Glycogen (alpha-1-4-linked glucan)
*Cyanophycin particles (arginine+aparagine storage)
*Polyphosphate bodies (Phosphate storage)
What is the Motility system used by Cyanobacteria? - ANS Motility:
*No flagella, but can glide, and move up and down in water.
-By using Gas vesicles
What is the Cell Wall in Cyanobacteria made from? - ANS Cell Wall:
*Peptidoglycan (like bacteria)
*Can have sheaths (gelatinous matrix)
What is the Habitat of Cyanobacteria? - ANS Habitat:
*Everywhere there is water!
-Freshwater, Marine, Terrestrial, Soil, Symbionts, Extremophiles (hot and cold)
What is the Reproduction system of Cyanobacteria? - ANS Reproduction:
*NO Sex- but can absorb environmental DNA, and have phages.
* Uses Asexual reproduction
-Binary fission -Endospores
-Exospores
, -Filaments can fragment
What is the Taxonomy of Cyanobactera? (Orders) - ANS *Chroococcales- unicellular, single or in
colonies (clumps)
*Pleurocapsales- endosore producing (baeocytes)
*Oscillatoriales- unbranched filaments, with hormogonia
*Nostocales- unbranched filaments, w/ heterocysts, akinetes, false branching-can form large
gelatinous colonies
*Stigonematales- True branching, w/ heterocysts, akinetes
What is the characteristics of Chroococcales? - ANS The order is characterized by single,
floating cells or colonies which are embedded to a matrix. There is also a lack of differentiation
between apical and basal structures.
What is the characteristics of Nostocales? - ANS It includes filamentous forms, both simple or
branched, and both those occurring as single strands or multiple strands within a sheath.
Some but not all members show a decrease in width from the base. Again, some but not all
have heterocysts.
--Can form large gelatinous colonies
What is the characteristics of Stigonematales? - ANS Includes filamentous strains that
produce hormogonia and exhibit true branching.
What is the system of Hormogonia in cyanobacteria? - ANS Hormogonia is:
*Method of vegetative propagation
*Programmed cell death
What is Heterocysts in cyanobacteria? - ANS *Heterocysts- cells with thick walls and no PSII
*Site of nitrogen fixation
