Q.1 What are the distinguishing features of Rhodophyceae. (2005, 09)
Related Questions -
Q. Write the characteristics of Rhodophyceae. (2012)
Q. What are main characters of Rhodophyceae? (2015)
Ans. Pigments: -
Chromatophores are red, blue containing pigments like red phycoerythrin and blue phycocyanin.
Reserve Food Material: -
Floridean starch a polysaccharide similar to starch.
Structure: -
The plants are simple filamentous to attaining considerable complexity of structure. Motile structures are not known. Except in few forms cells show protoplasmic connections.
Reproduction: -
Sexual reproduction is advanced oogamous type. The male organ produces non motile gametes and the female organ has a long receptive neck. After sexual reproduction special spores are produced.
Occurrence: -
Few forms are fresh water and others are marine.
Q.2 Write the name and systematic position of coenocytic alga studied by you. (2006)
Ans. Vaucheria: -
Systematic Classification: -
Class - Chlophyceae
Order - Siphonales
Family - Vaucheriaceae
Genus - Vaucheria.
Q.3 Name an alga which shows chantransia stage? (2006)
Ans. Batrachospermum.
Q.4 Distinguish between zoospore and aplanospore in an alga. (2007)
Ans. Zoospores are produced at the time of asexual reproduction. These contain flagella and may be uniflagellate to multiflagellate in different species of the algae. They are generally produced during favourable conditions and their number is usually more than one. Whereas aplanospores are non motile and are produced in aplanosporangia which are one or more in number.
Q.5 Name an alga whose zoospores have unequal flagella. (2009)
Ans. Ectocarpus-Of the two flagella in a zoospore , posterior one is smaller and whiplash type and the anterior one is longer and tinsel type.
Q.6 Draw ultrastructure of a pyrenoid in an alga. (2007)
Ans.
Q.7 Give two reasons how bryophytes differ from algae. (2007, 08, 09)
Related Question -
Q. Distinguish between Algae and Bryophytes. (2015)
Q. How Bryophytes differ from algae? (2017)
Q. Mention one important feature to distinguish algae from bryophyte. (2016)
Ans.
Q.9 Write classification of Batrachospermum and Sphagnum. (2007)
Ans. Batrachospermum: - (2008)
Division - Algae
Class - Rhodophyceae
Sub class - Florideae
Order - Nemalionales
Family - Batrachospermaceae
Genus - Batrachospermum
Sphagnum: -
Division - Bryophyta
Class - Bryopsida
Order - Sphagnales
Family - Sphagnaceae
Genus - Sphagnum
Q.10 Name an alga from which agar is obtained. (2008)
Ans. Gelidium cartilagineum.
Q.11 Name an alga which produces a ring of flagella in zoospore. (2008, 17)
Ans. Volvox.
Q.12 Which reduction division occurs in Ectocarpus. (2008)
Ans. Isomorphic alternation of generation.
Q.13 Name a fresh water alga of Rhodophyceae. (2008)
Other Related Questions -
Q. Name a fresh water red alga. (2017)
Ans. Batrachospermum.
Q.14 Name an alga which is popularly known as “WATER NET”. (2008)
Other Related Questions -
Q. Which algae is usually known as “Water Net”? (2017)
Ans. Hydrodictyon.
Q.15 Name an alga showing haplontic type of life cycle. (2007)
Ans. Chlamydomonas.
Q.16 Name any three economically important algae studied by you. (2007)
Ans. Chlorella, Fucus, Sargassum.
Q.17 Name an alga which possesses pit connection in vegetative cells. (2009)
Ans. Batrachospermum.
Q.18 Write the classification of Chlorella and Hydrodictyon. (2009)
Ans. Chlorella: - (2015)
Class - chlorophyceae
Order - Chlorococcocales
Family - chlorellaceae
Genus - Chlorella
Hydrodictyon: -
Class - Chlorophyceae
Order - Chlorococcales
Family - Hydrodictyaceae
Genus - Hydrodictyon.
Q.19 Write the name of two algae which grow by apical cell. (2009)
Ans. Ectocarpus and Dictyota(Brown algae-Phaeophyceae).
Q.20 Distinguish features of Phaeophyceae. (2010)
Related Question -
Q. Name the reserve food materials of Phaeophyceae. (2015)
Ans. Phaeophyceae - (Brown Algae): -
Pigments: -
Chromatophores are brown containing yellow fucoxanthin.
Reserve Food Material: -
Alcohol as well as polysaccharide and fats
Structure: -
The plants may be simple filamentous to bulky parenchymatous forms. Several plants attain a giant size with external and internal differentiation. In many cells characteristic fucoasn vesicles are present.
Reproduction: -
Sexual reproduction ranges from isogamous to oogamous. Motile gametes have two laterally attached flagella. Life cycle shows varied type of alternation of generation.
Occurrence: -
All plants but a few are marine.
Q.21 Cellwall components of Xanthophyceae and Rhodophyceae. (2010)
Ans. Xanthophyceae: -
Cellwall is made up of cellulose impregrated with silica.
Rhodophyceae: -
Cellwall is made up of cellulose consisting of pectic substances along with polysulphate esters.
Q.22 Define coenobium and give two examples. (2010)
Ans. Coenobium is a colony containing a fixed number of cells, with little or no specialization. They occur in several groups of algae.
Ex : Include - volvox and hydrodictyon.
Q.23 Write the classification of Polysiphonia and Porella. (2010, 13)
Ans. Polysiphonia Porella
Class - Rhodophyceae Division - Bryophyta
Sub class - Florideae Class - Hepaticopsida
Order - Ceramiales Order - Jungermannialed
Family - Rhodomelaceae Suborder - Jungermannineae
Genus - Polysiphonia Family - Porellaceae
Genus - Porella
Q.24 Give the names of two aquatic bryophytes. (2013)
Ans. (i) Riccia fluitans, (ii) Riccia natans
Q.25 Write the names of bryophyte that lack peristome teeth in their capsule. (2013)
Ans. Sphagnum
Q.26 Elaterophore is present in the ______ of ______ . (2013)
Ans. Sporophyte, Pellia
Q.27 What are phycobilisomes and where they occur? (2010)
Ans. Phycobilisomes are light harvesting anterrae of photosystem II in cyano bacteria and used algae. These occur in chloroplast.
Q.28 Why does the water of some lakes or rivers appear reddish in colour? Is it due to Gaudikov’s phenomenon or something else? Explain. (2011)
Ans. Some blue-green algae are capable of changing colour in response to the different color of light. This phenomenon is called “Gaiduknov phenomenon” or Complementary chromatic adaptation and is commonly exhibited by members of Oscillatoriaceae and Nostocaceae.
Q.29. How will you explain the ‘clump formation’ of gametes in Ectocarpus. (2011)
Ans. Fusion of gametes is quite interesting in Ectocarpus providing a prelude to sex-differentiation in algae. Though, the gametes are morphologically similar and the plants may be monoecious, but fusing gametes come from different plants. Of the two gametes, one is less active and becomes passive after a short while and behaves as a female gamete while other one is more active and is male. Such a fusion is an example of physiological anisogamy.
Beside, several male gametes cluster around one female gamete, each clings to it by long anterior flagellum but only one of them fuses to form a zygote.
Q.30. How are caps formed in the genus Oedogonium? Explain. (2011)
Related Question -
Q. Write short note on Capcells in Oedogonium. (2016)
Q. What are cap cells in Oedogonium. (2017)
Ans. For a pretty long time the newly formed wall remains floating in the cytoplasm. The elongation of thickening ring, after a certain limit, causes the rupture of outer non-elastic chitinous layer which leaves a cap-like covering in the apical region of the cell. The floating septum, before the rupture of outer cell wall, attains a permanent place near the edge of lower part of ruptured wall.
The so formed upper cell elongates swiftly while lower cell does not. As a result the upper daughter cell contains wall fromed chiefly from the stretched thickening ring and the lower cell contains the remanant parent cell wall.
The upper daughter cell with its apical cap is called cap cell and the lower daughter cell is the sheath cell. Each such division in a mature cell will produce one characteristic cap cell which may repeatedly divide and then the number of caps would correspond the number of divisions occurred in that cell.
Diagram showing various stages of cell division in O. borisianum (recent view). A - formation of thickening ring and shifting of nuclous, B- enlarging thickening ring, division of nucleus and initiation of cross wall formation (microtubules deposition) C, D stretching of cap cell and E - the newly formed cell. (Redrawn from Hill and Michaelis, 1968).
Q.31. What characteristics make Blue-green algae more closely related to procaryote. (2012)
Other Related Questions -
Q. What are procaryotic features of cyanophycean cell? (2017)
Ans. The cell of Blue green algae shows primitive structure, i.e. absence of true nucleus, definite plastids, mitochondria and endoplasmic, recticulum. This characteristics make Blue green algae more closely related to procaryote.
Q.32. How many flagella are found in antherozoids of Vaucheria. how does it differ from green algae in its food reserve material. (2012)
Ans. There are two types of flegella are found in antherozoids of vaucheria. The shorter flagellum is pantonematic type (tinsel type) while longer one is acronematic (whiplash type).
The reserve food material of vaucheria are oil and strach.The reserve food material of green algae is starch.
Q.33. On what basis the species of Oedogonium are segregated into two groups. (2012)
Ans. On types of male reproductive organ, the species of Oedogonium are segregated into two groups - Macrandrous and Nannandrous.
Q.34. Where reduction divisions occur in Ectocarpus. (2012, 17)
Ans. In Ectocarpus the gametophytes and sporophytes are similar morpholgocial and both are the capable of sexual reproduction by means of zoospores. Some of the plants are haplonts, others diplonts and still others show a regular alternation of generations of gametophytes and sporophytes.
Q.35. Distinguish between conceptacles and recepacles. (2012)
Ans. Receptacles are formed at the time of reproduction in the swollen ends of branched fronds and are characterised by the presence of numerous conical swellings or papillae formed due to underlying flask-shaped cavities called conceptacles. Conceptacles bear sex-organs and open outside through ostiole.
Q.36. Give the name of endophytic symbiotic algae reported in cycas and Anthoceros. (2013)
Ans. The name of endophytic symbiotic algae reported in Cycas and Anthoceros is blue green algae : Nostoc.
Q.37. Giving suitable examples define haplontic and Diplontic type of life-cycle pattern in algae. (2013)
Ans. (i) Zygote divides meiotically and forms motile or non-motile haploid spores, of which each develops into a new plant, e.g., Chlamydomonas and Ulothrix.
(ii) Zygote divides mitotically and forms a diploid plant. Later, plant reproduces by meiotic division and produces spores. Each spore develops into a new plant, e.g., Ectocarus.
Q.38. Terrestrial species of Vaucheria reproduce asexually by _____ and ______. (2013)
Ans. Zoospores, Aplanospores.
Q.39. Who gave the term algae? (2014)
Ans. Dr. F.E. Fritsch, famous international algologists gave the term algae.
Q.40. Name an alga found in India, that possesses male and female conceptacles. (2014)
Ans. Fucus
Q.41. In which alga, zoospores have many flagella in a ring? (2014)
Ans. Volvox
Q.42. In which genus autospores are formed? (2015)
Ans. Chlorella.
Q.43. Write the two economic importance of any algae. (2015)
Ans. Chlorella: -
(1) It contains a high percentage of protein, carbohydrates and vitamins. It is used for human consumptions as food.
(2) Another importance of Chlorella is that it yields an antibiotic chlorelline effective against bacteria.
Q.44. What are main photosynthetic pigments of chlorophyceae? (2016, 17)
Ans. Chlorophyll
Q.45. Which algae produces nuilocular and plurilocular sporangia? (2016)
Ans. Ectocarpus.
Q.46. Differentiate between cell walls of chlorophyceae and rodophyceae. (2016)
Ans. Chlorophyceae - Cell wall consists of Cellulose.
Rodophyceae - Cell wall is non cellulosic polysaccharides or with xylan, polyxylan, galactose and xylose.
Q.47. Name an algae which is used as food. (2018)
Ans. Chlorella.
Q.48. Name an algae in which dwarf males are produced. (2018)
Ans. Oedogonium.
Q.49. Name an algae which develops glomerule. (2018)
Ans. Batrachospermum.
Q.50. Name an algae in which sexual reproduction is absent. (2018)
Ans. Chlorella.