Essay Questions. 8 marks.

1. Compare Antheridial and Archegonial branches in Funaria.
2. Describe the internal structure of Funaria capsule.
3. Describe the internal structure of Pteris rhizome.
4. Describe reproduction in Pteris sporophyte.
5. Describe the reproduction in Pteris gametophyte.
6. Describe the internal structure of Cycas leaf-let.Mention xerophytic adaptations
7. What is Plant improvement?Describe its aims and objectives.
8. In which type of plants Mass selection,Pureline selection and Clonal selection
Can be performed.With examples,describe their advantages and disadvantages.
9. What is Hybridization?With suitable examples,describe different types in it.
10. Explain briefly steps involved in tissue culture technique?.
11. Describe Co2 fixation in C3 plants.
12. Describe Biochemical reactions occurring in Mitochondrial matrix.
13. What is Hybridization ?Describe various stages in it.
14. What is Glycolysis?Describe the sequence of reactions occurring in it.
15. What is Bio-technology?Describe the process of Recombinant DNA technology.
16. What is Selection?Describe various types,advantages and limitations in it.
17. Describe light phase in Photosynthesis.
18. Describe Electron transport occurring in Mitochondria cristae.
19. Describe the mechanism of Protein synthesis.

Short Answer Questions .4 marks.

1. Describe the cell structure of an autotrophic thallophyte.
2. Bring out the differences between Scalariform conjugation & Lateral conjugation in Spirogyra.
3. Bring out the differences between gametophore and protonema of Funaria.
4. Explain Transformation in Bacteria..
5. Differenciate between viroid and virion with two examples each.
6. Explain Field capacity and Permanent Wilting percent.
7. What are the important features and properties of Restriction endonucleases..
8. What is Hybrid vigour?Mention reasons for it.
9. Describe the role of induced mutations in crop improvement.
10. What are the differences between Auto tetraploids and Allotetraploids.
11. Differenciate between spontaneous mutations and induced mutations.
12. What is Emasculation?Why is it done in plants.
13. What is Synthetic genus?Giving two examples explain how they are to be formed.
14. Briefly describe Embryo sac culture and its advantages.
15. What is C-DNA and what are its advantages.
16. Describe three types of Transpiration.
17. “Transpiration is a necessary evil”-explain.

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18. With a neat labeled diagram describe the structure of a Bacteriophage.
19. Bring out the differences between Rust and Smut disease.
20. Discuss the role of Auxins in plants.
21. Describe the importance of tissue culture in plants.
22. Describe various horizons in the soil as seen in soil profile.
23. What is the main force causing Osmosis.Explain it with experiment.
24. Describe the role of Gibberellins in the field of Agriculture and Horticulture.
25. Describe the disease and control measures of plant disease,showing symptoms when panicle emerges out.
26. Describe a Bacterium cell.
27. Classify Viruses based on the nature of host.
28. Describe the symptoms of Blast of Rice disease.
29. Describe the opening and closing mechanism of stomata in plants.
30. Describe the disease symptoms of Citrus canker.
31. Describe various green manure fertilizers.
32. Describe the role of Gibberellins in plants.
33. Describe Dioecious conjugation in Spirogyra.
34. Bring out the differences between C3 & C4 plants in Co2 fixation.
35. Write the name of pathogen,name of disease causing in sugarcane.Describe the symptoms and control measures.
36. Write about active absorption of ions..
37. What is Ascent of Sap?How can you explain it in tall trees,by Cohesion and Tension theory.
38. Wite about Bio-fertilizers.
39. Write about the physiological effects of Cytokinins in plants.
40. What are transgenic plants?What are their advantages.
41. Based on shape and arrangement classify various types of Bacteria.
42. Write short notes on conjugation in Bacteria.
43. What is Kranz anatomy?What is its importance in plants.
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VSA Questions.& answers

1. Bring out the difference between holdfast and vegetative cell of Spirogyra?
holdfast=without chloroplast,cannot divide.
Veg.cell=chlorophyllous,shows cell division.
2. Why Spirogyra is called Pond silk and Pond scum?
Pond silk—pectin cellwall becomes mucilage forming slimy to touch.
Pond scum—formsfree floating entangled mass of fine filaments.
3. What will happen in Spirogyra when gametes fail to fuse in conjugation.
Gamete form resting spores with thick cell wall by parthenogenesis.
4. Where in zygospores seen in Spirogyra during isogamous and physiologically
anisogamous conjugation.
Isogamous=filaments show empty cells,zygospore in conjugation tubes.
Physiological anisogamy=Male filament with empty cells,female filament with zygospores.
5. Why Rhizopus is called Bread mould and Black mould?
Bread mould=forms cottony mycelium on stale bread.
Black mould=mycelium produces dark colored sporangia.
6. Why Rhizopus is called Pin mould and Weed of Laboratory?
Pin mould=sporangiophore with globose sporangia looks like pin head.
Weed of laboratory=commonly contaminates microbial cultures.
7. What is meant by “zygophore”,”zygote”,”zygospore”,”zygosporangium”?
Zygophore=hypha that forms progametangium
Zygote=formed by the fusion of two gametangia.
Zygospore=the diploid spore formed in the zygosporangium.
Zygosporangium=formed by the union of two gametangia,develops dark,thick outer coat.
8. Differenciate Paraphysis from apophysis?
Paraphysis=filamentous,multicellular,uniseriatesterile hairs intermixed with antheridia and archegonia in Funaria.
Apophysis=assimilatory basal part of capsule in Funaria.
9. What is calyptra in Funaria? What is its function ?
Around the growing embryo,venter wall remains as protective cover forming
Calyptra.It forms a lid over the capsule.
10. What is a Dictyostele?
The dissected stele embedded in parenchymatous ground tissue.ex:Pteris rhizome.
11. What is transfusion tissue?
Special lignified cells formed around the vascular bundle form primary transfusion cells,which laterally develop in the mesophyll form secondary transfusion tissue with bordered pits.ex:Cycas leaf-let.
12. What is false indusium?
The infoldings of sporophyll protecting the sori .Ex:Pteris.

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13. What are Girdle leaf traces?
Indirect leaf trace from the vascular bundle,bifurcates,encirculates stele,
before entering the leaf.
14. What doyou understand byPseudomesarch vascular bundle.?
Vascular bundle with exarch centripetal xylem,& endarch,centrifugal xylem.
15. Which organisms are refered to as “Scavengers of Nature” and why?
Bactria decompose dead decaying plants and animals,converting complex organic matter into simple substances.
16.What is Lysosome ?What is its function?
Enzyme secreted by Bacteriophage,to degenerate the host cellwall to inject its
nuclic acid.
17. Differenciate between pathogenesis and pathogenicity?
Pathogenesis=sequence of metablic changes bringing out the disease.
Pathogenicity=capability of pathogen causing disease.
18. Name the fungi causing Bengal famine and Irish famine?
Bengal famine=Brown leaf spot.Helminthosporium oryzae.
Irish famine=Potato blight.Phytophthora infestans.
19. Why does the juice from infectedsugarcane give bad odour?
Sucrose in infected cane turns to glucose and to alcohol .
20. How Mushrooms are helpful in providing food to plants in forests?
Mushrooms disintegrate the plant material on which they grow and make the nutrients available to the plants in forests.
21. What is crop rotation ?Give one example.
Planting unrelated,resistant crops,from season to season,to avoid pathogen specificity.ex:damping off.
22. Why is Blast of Rice called “Neck Blast”?
Infected neck of the panicle is blackened due to grey,fluffy mycelium.
23. Differentiate between Litter and Guff?
Litter=recently fallen organic debris on the ground.
Duff=partially decomposed organic matter beneath the Litter.
24. Which type of soil is best suited for plant growth and why?
Loamy soil.equal ratios of sand,silt and clay.Much water holding capacity,aeration and rich in minerals.
25. Define Imbibition?Why do Pea seeds show more imbibition than wheat seeds?
Absorption of water by hydrophilic colloids is called Imbibition.
Proteins have high imbibing capacity than carbohydrates.Proteinaceous Pea seeds swell more on imbibition than starchy wheat grains.
26. Define Symport and Antiport?
Symport=transport of anions and cations in the same direction by carriers.
Antiport=transport of ions in opposite direction.
27. Define Absorption spectrum and Action spectrum?.
Absorption spectrum=a graph showing the absorption of lightby pigments at different wavelengthsIt is measured by Sphectrophotometer.
Action spectrum=a graph showing the rate of photosynthesisat different wavelengths..
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28. What is Colchicine?Write its source and use.
Alkaloid used in doubling the chromosome number.It is obtained from the corms of Colchicum autumnale.
29. What is Triticale?
Synthetic genus made by a cross between Trticum aestivum and Secale cereale
developed by Polypliody breeding.
30. List out different selection methods for hybridization in self pollinated crops.
Pedigree method,Bulk method,Back cross method.
31.What is RUBISCO?Comment its importance in photosynthesis?
RUBISCO=Ribulose 1,5,bis phosphate carboxylase/oxygenase.
Most abundant soluble protein in plant leaves.Helps in the reaction
Of Co2 acceptence by RuBP to form stable compound PGA.
32.What is micropropagation ?
In vitro growing of plant cells, tissues and organs .
33.What is the nutritive value of mushrooms?
Vit.B,Folic acid,vit.B12,Pantothenic acid,ascorbic acid,amino acids
Lysine,Tryptophane,precursors of vit.A and D,minerals P,K,Fe,Cu.
34.Define Single Cell Protein and give two examples .
The purified cell biomass of unicellular organisms forming protein source.
Spirulina,Yeasts.
35. What is rDNA technology?Give two examples of its application in the field of
medicine.
Isolation of specific gene and insertion of it in another organism through
vector to express its native characters.ex.humilin,gene therapy.
36. Differentiate turgid cell from flaccid cell.
The cell with turgor pressure is called turgid cell.The cell with reduced turgor
Pressure due to loss of water is called flaccid cell.
37. Which substance is called connecting link betweenGlycolysis and Kreb’s
cycle?How many carbon atoms are present in it?.
Acetyl CoA. 2 carbon atoms..
38. What are the two objections for Cohesion-Tension theory.?
a)embolism=formation of gas bubbles in xylem obstructing the continuity
of water.b)tracheids are the conducting channels.During evolution vessels
eliminate tracheids
39. What is the difference between Transpiration and evaporation?
Transpiration=loss of water in the form of water vapour from the aerial
Parts of the plant.
Evaporation=loss of water in the form of vapour directly from water
Into the atmosphere.
40. How many macroelements are required for plant growth.What are they.
9-C,H,O,N,P,K,Ca,Mg,S.
41. Define apoenzyme and holoenzyme.
Apoenzyme=protein part of enzyme.
Holoenzyme=apoenzyme and cofactor together called.
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42. Mention the primary acceptor of Co2 in C3 and C4 plants.
C3 plants=RuBP(Ribulose Bis Phosphate)
C4 plants=PEP(Phospho Enol Pyruvate).
43. Why C4 plants are more efficient than C3 plants?
C4 plants assimilate two or three times more Co2 than C3 plants.
Photorespiration will not take place in C4 plant
44. Name the pigment present in the root nodule of legumes and give
Its function.
Leghaemoglogin.it regulates theavailability of Oxygen,protecting the
Nitrogenase in the bacteroid.
45. “The Genetic code is non-overlapping” elaborate.
No single base can take part in the formation of more than one code.
46. What is Richmond-Lang Effect.
The ability of cytokinins to delay the process of senescence.
47. Where does Oxidative Phosphorylation occur?What are its components?
On inner mitochondrial membrane. 3 components namely FMN,FAD,Cyt a, Cyt b, Cyt c..
48. Differentiate Plasmids from Cosmids.
Plasmids=small circular DNA,with 25to30 genes,extra nuclear in protoplasm,
With antibiotic resistant genes.
Cosmids=plasmids with cos sites that canbe introduced in phage capsids.
49. Explain Hill reaction.
Lysis of water releasing O2,in the presence of hydrogen acceptor,
When chloroplasts are illuminated.
50. Define diazotrophy? Give example..
Dinitrogen fixation by living organisms is called diazotrophy.Nostoc,Anabaena..
51.Write terminator codons and their function.
UAA,UAG,UGA.they help in terminating the polypeptide chain synthesis.
52. What is molecular farming?
Using Transgenic plants as bioreactors for getting specialized medicines,chemicals,and antibiotics.
53. What are nif genes?.What is the enzyme coded by it?
Prokaryotic cell genes responsible for biological nitrogen fixation are called nif genes. Dinitrogenese.
54. Define the turn over number of an enzyme.
Number of moles of substrate converted into product,by one mole of enzyme per minute.
55. Differentiate the cell structure of Spirogyra and Rhizopus.
Spirogyra=uni nucleate,cellulose cell wall,starch reserve
Rhizopus=coenocyte,chitin cell wall,Gycogen,oil globules reserve.

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56. How can you differetiate the antheridial cluster from archegonial cluster
In Funaria.
Antheridial cluster=terminal,with perigonium form moss flower,lateral later.
Archegonial cluster=lateral,with perichaetium,terminal later.
57. What do you understand by “peristome”
Two whorls of 16 hygroscopic teeth in each circle,in operculam of Funaria
Capsule ,helping in the dispersal of spores.
58. What do you understand by the terms-annulus and stomium?
Annulus=ring of vertically elongated cells helping in the dehiscence of
Sporangium in Pteris.
Stomium=small,flat,thin walled ,radially elongated cells,with upper epistomium and lower hypostomium,helping in the cleavage of sporangium
59.Mention the difference between the anatomy of coralloid root and normal root.
Normal root=resembles dicot root,xylem diarch or tetrarch.
Coralloid root=shows algal zone with Nostoc,Anabaena(blue green algae),
Xylem triarch.
60. Which bacterium produces “gobar gas” and how?
Methanococcus,Methanobacillus anaerobically ferment dung and produce
Methane gas,(gobar gas).
61. Define Shelf life and Vase life ?Give the hormone substances promoting it?
Shelf life= storage period without loss of freshness in vegetables.Cytokinin.
Vase life=period of freshness of flowers in a flower vase. BAP.
62. Explain the term Amphidiploid.
Allotetraploid containing two diploid sets of chromosomes of two different
Species or genera of the same family.
63. What are the causes and remedies of inbreeing depression?
Considerable loss of vigour in hybrid due to continuous self pollination
Segregation of genes and homozygosity are causes.
Crossing in bred lines,heterozygosity are remedies.
64. Write an account on interspecific hybridization.
Crossing two species of the same genus.Disease and drought resistance canbe
Achieved.Ex;Red plum in tomato=Lycopersicum esculentum x L.pimpinellifolium.Devi Raj cotton=Gossypium hirsutum xG.arboreum.
65. Mention the important varieties,type of hybridiztion by which Jaya,Padma
Varieties in Rice are achieved.
Intervarietal(intraspecific) hybridization.
T.N.1 x T.141 =Jaya.;T.141 x T.N.1 =Padma.
66. Who coined the word Heterosis.State the imporatant causes for it.
The superiority of the hybrid over the parents in size and vigour.
G.H.Shull coined Heterosis.
Causes:dominance hypothesis;over-dominance hypothesis.

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67. How are artificial ployploids produced?
a)cold treatment of zygote in dividing state. b)applyingacenaphthene,colchicines,coumarin to vegetative,floral buds.
c) subjecting vegetative,floral buds to X rays.
68. How are Mutations induced?
X-rays,alpha-rays,beta-rays,gamma rays(ionizing),UV rays(non-ionizing)
Colchicines,nitrogen.mustard gas,formaldehyde,ethyl methane sulphate,
Methyl methane sulphonate,malic hydrazide(chemical mutagens)
Induce mutations.
69. Define RQ?Why RQ value for fats is less than zero?
The ratio of Co2 liberated to the O2 absorbed is called R.Q.
For fats,Co2 released is less than O2 consumed.R.Q=57/83=0.69.
70. Name the auxins that act as herbicides.
2,4,dichlorophenoxy acetic acid (2,4-D).
2,4,5-trichloro phenoxy acetic acid (2,4,5-T).
71. What is meant by “triple response growth”?
Inhibiting elongation of growth,inducing lateral growth and causing transverse geotropism by Ethylene.
72.Why Spirogyra is slimy when kept in water?
Pectose part of the cell wall becomes mucilage sheath with water.
73. Mention the major types of cultivated mushrooms in India.
White button mushroom—Agaricus bisporus.
Oyster mushroom--- Pleurotus sojar-caju.
Paddy straw mushroom-- Volvariella volvacea.
74. Why the rate of transpiration is more in Sorghum than in maize ?
Sorghum has more root-shoot ratio than maize.Rate of transpiration increases with an increase in root-shoot ratio.
75. What is senescence?How can leaf senescence can be delayed?
Aging process in plants.Cytokinins BA,BAP.
76. Define Glycocalyx? Into how many layers it is differentiated?
Layer lying outside the Bacterial cellwall is called Glycocalyx.Two layers.Polysaccharide made loosely formed Slime layer,thick tough Capsule layer.
77. Describe apogamy in Pteris.
Apogamy is the development of sporophyte from gametophyte without syngamy.Sporophytes will be haploid.
78. Define single cell protein ?Give two examples.
The purified dried cell biomass of unicellular organisms forming protein source is called SCP.Spirulina,Chlorella,yeasts.
79. What is meant by apical dominance?Name the phytohormone that causes it.
Actively growing apical buds dominate and inhibit the growth of axillary buds.
Auxins show apical dominance.

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80. What is the difference between active and passive absorption.
ATP is utilized in active absorption.,not in passive absorption.
81. What is meant by Heterothallism?Who discovered it first in Rhizopus?
It is the condition of the mycelium ,morphologically alike,but physiologically different in having two different strains.
A.F.Blakeslee observed it in Rhizopus stolonifer.
82. Define Emerson enhancement effect?
When shorter and longer wavelengths are used simultaneously the
Photosynthetic yield is more,than when the individual lenths are used.
83. Write the name of the alkaloid that enable the doubling of chromosome
number.Where from it is obtained.
Colchicine prevents the spindle formation during metaphase of meiosis
And enables doubling of chromosomes.it is derived from the corms of
Colchicum autumnale.(Fam:Liliaceae).
84.Write any two deficiency symptoms of Potassium.
Chlorosis followed by necrosis in margins and tips of leaves.
Shortened internodes.Phloem mobile ,first appear in older leaves.
85. Write about the Paraphyses in Funaria.
Intermixed with antheridia and archegonia multicellular,uniseriate,filamentous sterile hairs are called paraphyses.They conserve moisture and protect the organs.

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