1st PUC Biology Question Bank Chapter 3 Plant Kingdom

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Karnataka 1st PUC Biology Question Bank Chapter 3 Plant Kingdom

1st PUC Biology Plant Kingdom NCERT Text Book Questions and Answers

Question 1.
What is the basis of the classification of algae?
Classification of algae is based upon photosynthetic pigments.

Question 2.
When and where does reduction division take place in the life cycle of a liverwort, a moss, a fern, a gymnosperm and an angiosperm?
Reduction division occurs in gametic cells. The main aim is to halve the number of chromosomes for the purpose of fertilization.

KSEEB Solutions

haplo-diplontic in nature, sporophyte generation is represented only by one-celled zygote. Reduction division results in information of haploid cells. Haploid spores mitotically divide to form gametophyte (main plant body). During sexual reproduction male and female sex, organs may be present or the same or different thalli.

A moss:
Reduction division in moss occurs similar to liverwort gametophyte which is a predominant stage hence haplodiplontic. It consists of 2 stages. The first stage is the protonema stage, which develops directly from. a spore. The second stage is the leafy stage which develops from secondary protonema as a lateral bud. This stage bears sex organs.

A fern:
fern is diplontic in nature. A dominant sporophyte body is present. Sporophytes bear sporophylls. Sporophylls (sporangia) produce spores by meiosis in spore mother cells. The spore geminate to give rise to inconspicuous small but multicellular free-living, mostly photosynthetic thalloid gametophytes called prothallus.

A Gymnosperm:
diplontic in nature. Gymnosperms are heterosporous as they produce haploid microspores and megaspores. The two kinds of spores are produced within sporangia that are borne on sporophylls which are arranged spirally along an axis to form lax or compact strobili or cones. The microspores develop into a male gametophytic generation which is highly reduced and is confined to only a limited number of cells. Megaspores develop into a female gametophyte generation.

An Angiosperm:
Diplontic in nature, male sex organs in a flower are the stamen. Each stamen consists of a slender filament with an anther at the tip. The anthers, following meiosis, produce pollen grains. The female sex organ in a flower is the pistil or carpel. Pistil consists of an ovary enclosing one or many ovules. Within ovules are present highly reduced female gametophytes termed embryosacs.

Question 3.
Name three groups of plants that bear archegonia. Briefly describe the life cycle of any one of them.

KSEEB Solutions

Question 4.
Mention the ploidy of the following:
protonemal cell of a moss; primary endosperm nucleus in dicot, leaf cell of a moss; prothallus cell of a fern; gemma cell in Marchantia; meristem cell of monocot, ovum of a liverwort, and zygote of a fern.

  • protonemal cells of a moss → haploid, developed from spores
  • primary endosperm nucleus of dicot → diploid, formed after fertilization
  • leaf cell of a moss → haploid, develops from protonemal cells
  • prothallus cell of a ferm → haploid, bears male and female sex organs gametophyte
  • gemma cells in Marchantia → diploid, asexual reproduction cells
  • meristem cell of monocot → diploid, somatic cell
  • ovum of a liverwort → hiploid, female egg
  • Zygote of a fern → diploid formed after fertilization.

Question 5.
Write a note on the economic importance of algae and gymnosperms.
Economic importance of algae: Algae are useful to man in a variety of ways.

  1. At least half of the total carbon-dioxide fixation on earth is carried out by algal through photosynthesis.
  2. Being photosynthetic they increase the level of dissolved oxygen in their immediate environment.
  3. They are of paramount importance as primary producers of energy-rich compounds that form the basis of the food cycles of all aquatic animals.
  4. Many species of Porphyra, Laminaria, and Sargassum are among the 70 species of marine algae used as food.
  5. Certain marine brown and red algae produce large amounts of hydrocolloids e.g., algin (of brown algae) and carrageen (of red algae) are used commercially.
  6. Agar, one of the commercial products obtained from Gelidium and Gracilaria is used to grow microbes and in preparations of ice-creams and jellies. Chlorella and Spirulina are unicellular -algae, rich in proteins, and are used as food supplements even by space travelers.

Economic importance of Gymnosperms:

  1. Conifers provide an enormous amount of softwood for the construction, packing, plywood, and paper industry.
  2. Turpentine and rosin are obtained from the resin of Pinus. Turpentine is used as a solvent in paint and polishes. It is used medicinally for pain, bronchitis, and intestinal worms. Rosin is used in waterproofing and sealing joints.
  3. The wood of a number of conifers is used in the manufacture of paper.
  4. Sawdust of conifers is used in making linoleum and plastics.
  5. Seeds of Pinus gerardiana (chilgoza) are edible.
  6. Ephedrine a drug obtained from Ephedra is used for curing respiratory trouble and asthma.

KSEEB Solutions

Question 6.
Both gymnosperms and angiosperms bear seeds, then why are they classified separately?
The seeds of gymnosperms are naked whereas the seeds of angiosperms are covered by fruits.

Question 7.
What is heterospory? Briefly comment on its significance. Give two examples.
Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and micro (small) spores, are known as heterosporous. The megaspores and microspores germinate and give rise to female and male gametophytes, respectively. The female gametophytes in these plants are contained on the parent sporophyte for variable periods. The development of the zygotes into young embryos takes place within the female gametophytes. This event is considered an important step in evolution leading to the seed habit.

Question 8.
Explain briefly the following terms with suitable examples:-
(i) protonema
(ii) antheridium
(iii) archegonium
(iv) diplontic
(v) sporophyll
(vi) isogamy
(i) Protonema:
The predominant stage of the life cycle of a moss is the gametophyte which consists of two stages. The first stage is the protonema stage, which develops directly from a spore. It is a creeping green branched form frequently a filamentous stage.

(ii) Antheridium:
Antheridium is a haploid structure producing and containing male garnets. Antheridium is the male sex organs of lower plants such as pteridophytes, bryophytes, etc., Antheridium produces antherozoids. These antherozoids are released into the surrounding such that they come in contact with female sex organs (archegonium)

(iii) Archegonium:
Archegonium is a multicellular organ of the gametophyte phase of certain lower plants. It produces and contains Ovum or female gametophyte. Archegonium is a female sex organ. Archegonium is present on the surface of the plant thallus. Archegonium is flask shaped. When Antherozoids come in contact with eggs in Archegonium they form Zygotes.

(iv) diplontic:
Type of life cycle in plants where diploid sporophyte is a dominant, photosynthetic independent phase of the plant. The gametophytic phase is represented by the single to the few-called haploid gametophyte. All seed-bearing plants (gymnosperms and argiosperms) follow this pattern.

(v) sporophyll:
In pteridophytes main plant body is the sporophyte. The sporophytes bear sporangia that are subtended by leaf-like appendages called sporophylls. In some cases sporophylls may form distinct compact structures called strobili or cones. The sporangia germinate to give rise to the inconspicuous, small but multicellular prothallus.

KSEEB Solutions

(vi) isogamy:
Isogamy refers to form of sexual reproduction involving two gamets similar in size and appearance. Chiamydomonas’s gametes have same size and are flagellated Spirogyra’s gametes are similar in size but don’t have flagella.

Question 9.
Differentiate between the following:
(i) Red algae and Brown algae
(ii) Liverworts and Moss
(iii) homosporous and heterosporous pteridophyte
(iv) syngamy and triple fusion

Brown algae Red algae
(a) colour due to the presence of fucoxanthin colour due to the presence of phycoerythrin rin.
(b) Chlorophyll a,c are present Chlorophyll a, d are present
(c) stored food mannitol and laminarin stored food Floridian, starch etc.,
(d) cell wall is made up of cellulose and algin cell wall is made up of cellulose, pectin, and polysuiphate esters
(e) unequal flagella are present flagella are absent

(ii) Liverworts and Moss

liverworts moss
(a) gametophyte consists of single-stage gametophytes consists of two stages (Protonema and leafy stage)
(b) Asexual reproduction is by fragmentation of thalli Asexual reproduction is by fragrnentation& budding
in secondary protonema
(c) rhizoids are absent rhizoids are present
(d) example: Marchantia example: Funaria polytrichum

(iii) Homosporous and Heterosporous pteridophyte

Homosporous Heterosporous pteridophyte
(a) all spores produced of similar kinds pteridophyte two kinds of spores macro & microspores are produced
(b) majority of pteridophytes are homosporous Very few heterosporous pteridophytes
(c) e.g.: Psilotum eg: selaginella, Salvinia

(iv) Syngamy and triple fusion

Syngamy Triple fusion
(a) male gametes fuse with the egg cell male gamete fuses with diploid secondary nucleus
(b) zygote is produced tripioid primary endosperm nucleus is produced (PEN)
(c) zygote is diploid PEN is triploid
(d) zygote develops into an embryo PEN develops into endosperm which provides nourishment to developing embryo

Question 10.
How would you distinguish monocots from dicots?
The dicotyledons are characterized by having two cotyledons in their seeds while monocotyledons have only one cotyledon in their seeds.

Question 11.
Match the followings (column I with column II)

Column I – Column II
(a) Chiamydomonas – (i) Moss
(b) Cycas – (ii) Pterldophyte
(c) Se/ag/ne/la – (iii) Algae
(d) Sphagnum – (iv) Gymnosperm
a – iii
b – iv
c- ii
d- i

Question  12.
Describe the Important characteristics of gymnosperms.
Gymnosperms: The seed-forming vascular plants that produce seeds but no fruit are called gymnosperms.
General characters:

  1. Most such plants are evergreen
  2. Most primitive seed-bearing plants.
  3. Leaves may be of two kinds-foliage leaves and scale leaves.
  4. Large, tall, and woody trees.
  5. Exhibit polyembryony.
  6. Have no ovary wall, seeds are naked.
  7. Have two types of branches – dwarf shoots and long shoots,
  8. The ovules are orthotropous.
  9. Sexual reproduction is of oogamous type.
  10. Fertilization needs no water.

1st PUC Biology Plant Kingdom Additional Questions and Answers

1st PUC Biology Plant Kingdom One Mark Questions

Question 1.
Which type of food reserve is present in green algae?

Question 2.
Why the Plant body of Bryophytes is Game-tophyte?
Plant body of bryophyte produces gametes in their sex organs. So it is gametophyte.

Question 3.
Name the male Sex Organ of Bryophyte.

KSEEB Solutions

Question 4.
Name the class to which Riccla belongs.

Question 5.
Which filamentous structure does appear in mosses due to the germination of spores?

Question 6.
What is Sporophyte?
It is the plant body or generation that produces spores by the asexual method.

Question 7.
What is thallus? (Mandya 05, D.K. 2007)
The thallus is the undifferentiated plant body characteristic of most bryophytes.

Question 8.
Write a note on Archegonia. (Mysore 05)
These are flask-shaped female sex or¬gans found in the gametophyte of bryophytes and pteridophytes.

Question 9.
Assign the following plant to their respective group
(i) Anthoceros
(ii) Funaria (D.Kannada 2006)
(i) Anthoceros – Bryophyte – thalloid and dominant gametophyte
(ii) Funaria – Bryopsida – Sporophyte parasitic on the gametophyte.

Question 10.
Give a reason for the following.
Bryophytes require water for reproduction. (D.Kannada2008)
The sperms of bryophytes are motile, hence require water for swimming.

Question 11.
Give reason;
Bryophytes are amphibians of the plant kingdom. (D. Kannada 2009)
Even though bryophytes live on land they need water for fertilization.

Question 12.
What are Tracheophytes?
They are the group of plants and plant organs that contain xylem and phloem like tissues

Question 13.
Which is the dominant phase in the life cycle of Pteridophyta?
The diploid sporophyte is the dominant phase of Pteridophyta.

Question 14.
What is the other name of Prothallus?

Question 15.
What is Archegonium?
The female sex organ of Bryophytes, as well as pteridophytes, is called archegonium.

Question 16.
Define circinate vernation. (Belgaum 05)
Circinate vernation is the spring-like coiled nature of young leaves of ferns.

Question 17.
Give reason;
Pteridophytes are lower vascular cryptogams. (D. Kannada 2009)
They possess xylem and phloem but are seedless plants.

Question 18.
What are Strobili?
The reproductive organs of gymnosperms are called strobili / cones.

Question 19.
Why the Sporophyte of Gymnosperm is heterosporous 7
The sporophyte produces two types of spores like microspores and megaspores so it is heterosporous.

Question 20.
Mention the class of Cycas. (D. K 2008)

KSEEB Solutions

Question 21.
What are mega and Microsporophylls?
Megasporophylls are the structural components of female cone. They produce megasporangium or ovules. Microsporophylls are the structural components of the male cone. They produce microsporangia.

Question 22.
Assign Cycas to its respective class. (B’lore North, South, Tumkur, Mandya 05)
Cycas – Class Cycadopsida

Question 23.
Give the meaning of term Gymnosperm. (D. Kannada 2007)
Gymnos (naked) spermia (seeds). Gymnosperms are therefore called naked seed plants.

Question 24.
What are Staminodes?
Sterile stamens are staminodes.

Question 25.
What is a Carpel?
The unit of pistil is a carpel.

Question 26.
What is Adelpy?
If filaments of stamens are united and anthers are free then it is called adelpy.

Question 27.
What is meant by Thalamus?
swollen apical part of the pedicel on which the floral parts are arranged is called thalamus.

Question 28.
Which Plant produces largest flower?

Question 29.
What is Perianth? (B’lore North 04)
is the floral whorl, where the distinction between calyx and corolla cannot be made.

Question 30.
What are Tepals? (Udupi2006)
Units of perianth are tepals.

Question 31.
What is Aestivation? (Gulbarga 04, D.K. 05,07, Darwad 05, Udupi 06, Tumkur2008)
The mode of arrangement of sepals and petals in the flower bud is called aestivation.

Question 32.
What is a Torus?
The swollen apical part of the pedicel on which the floral parts are arranged is the torus or thalamus.

Question 33.
What Is a Pedicel?
Flower stalk is called pedicel.

Question 34.
What is a Sessile flower?
Flower without pedicel is sessile flower.

Question 35.
What is Persistent Calyx?
If calyx remains even after the formation of fruit is called persistent calyx.

KSEEB Solutions

Question 36.
Define the term Hypogyny? (Shimoga 05)
If the thalamus is convex/conical/ flat such that the gynoecium occupies topmost position and Calyx, Corolla and androecium originate below it, is called hyponymy.

Question 37.
What is meant by Placentation? (Gulbraga 2005)
The method of arrangement of ovules on the placenta in the ovary is called placentation / Arrangement of ovules on the placenta in the ovule is termed placentation.

Question 38.
What Is meant by Eplpetalous Corolla”
If stamens are attached to petals, then the stamens are called epipetalous.

Question 39.
What is double fertilisation?
Fusion of one of the male gametes with the egg are the second male gamete with the secondary nucleus is called double fertilization. OR The participation of two male gametes in two fertilization is called double fertilization.

Question 40.
What is anemophily / omithophily? (Udupi 2006)
Pollination by wind is called anemophily. Pollination by birds is called omithophily.

Question 41.
What is synandry? (M.Q.P.Udupi 2006)
’The condition in which the anthers and filaments are fused is termed synandry.

Question 42.
What is Parthenocaic fruits? (Dharwar04)
It is a seedless fruit formed without the process of fertilization.

Question 43.
What is a superior ovary? (B’lore North 05)
If the’ ovary is placed above the thalamus (Hypogyny) it is called superior ovary repeated

Question 44.
What name is given to male and female sex organs of green algae?
Antheridia and Qogooia.

Question 45.
Name the structure that fixes the brown algae to the substratum.
Hold fast.

Question 46.
Which class of algae doesn’t have any motile stage? r

Question 47.
Which is the first cell of gametophytes and sporoph/’e in the life cycle of a liverwort?
Spore and zygote.

Question 48.
Why do bryophytes live in damp/moist shady places?
Bryophytes require water for fertilization purposes.

Question 49.
Name the dominate phase of life cycle of a fers.

Question 50.
When are where does meiosis occur in pteridophytes?
Meiosis occur in spore mother cells dur¬ing spore formation.

Question 51.
What is the scientific name of horsetail?

Question 52.
Define palliation.
Pollination can be defined as a process in which pollen grains are transferred from the another to the stigma.

1st PUC Biology Plant Kingdom Two Marks Questions

Question 1.
Mention the Sex organs of Bryophytes. (D. Kannada 2009)
Antheridia (male sex organs) and Archegonia (female sex organs).

Question 2.
What is numerical taxonomy?
Numerical Taxonomy is based on all observable characteristics. Number and codes are assigned to all the characters and the data are then processed. In this way, each character is given equal importance and at the same time, hundreds of characters can be considered.

Question 3.
List any four differences between Dicot and Monocot Plants. (Tumkur 2008)

  • Dicot plants produce tap roots Monocotstos produce fibrous roots.
  • Dicot plants contain reticular ventated leaves. The leaves of monocots show parallel venation.
  • Dicots produce seeds with two cotyledons. Monocots produce seeds with single cotyledon
  • In dicots stele is eustele. In monocots stele is atactostele.

KSEEB Solutions

Question 4.
Differentiate between Hypogynous and epigynous flowers.

  • In hypogynous flower, the thalamus is convex or flat and gynoecium occupies the topmost position and other floral parts originate below. In epigynous flower, thalamus is cup-shaped enclosing ovary and other floral parts will be arranged above it.
  • In hypogynous flower, ovary is superior. In epigynous flower, the ovary is inferior.

Question 5.
What is Aestivation? Mention two types of Aestivation. (Belgaum 2005)
Mode of the arrangement of sepals petals or – tepals in a bud condition is called aestivation. Types of aestivation are

  • valvate
  • Imbricate.

Question 6.
What is the unique feature of bryophyte in comparison to other plant groups? Discuss.
In Bryophytes, zygotes do not undergo reduction division immediately. They produce a multicellular body called a sporophyte. The sporophyte is not free-living but attached to the photosynthetic gametophyte and derives nutrition from it.

Question 7.
Write any two differences between androecium and gynoecium. (Belgaum 04)

  • It is the male reproductive structure.
  • It is composed of stamens.


  • It is the female reproductive structure.
  • It is composed of carpels.

Question 8.
What is meant by isogamy? Give an example.
‘Isogamy is a phenomenon in which both male and female gamete are similar in size, structure of physiology e.g.: Chlamydomonas, Ulothrix.

Question 9.
What are gemmae? Name two plants that produce gemmates/Gemmae are green, multicellular, asexual buds, which develop in small receptacles called gemma cups on the thallus. e.g. Marchantia, Riccia.

Question 10.
Term prothallus is monoecious. Justify.
A fern is homosporous and produces only one type of spore Each spore germinates into a prothallus that are both antheridia and or archegonia a and hence monoecious.

Question 11.
What are spermatophytes? Give examples.
Spermatophytes are plants which produce seeds. e.g.: Gymnosperrn and Angiosperms.

Question 12.
How do gametophytes of pteridophytes different from those of gymnosperms?

Gametophyte of pteridophytes Gametophyte of gymnosperms
(a) Gametophyte is independent or free living. (a) Gametophyte depends on sporophyte
(b) prothallus, is monoecious & beass both antheridium& archegonium (b) Male & female gamete phyte are a district
(c) Water is necessary  for male gamete to swim towards female (c) water is not necessary for fertilization as male gamete are carried in pollen tubes to female garnets

Question 13.
Why is the endosperm of angiosperms triploid?
Endosperm of angiosperms is product of triple fusion. Two haploid polar nuclei in the centre of the embryo sac free to form a diploid secondary nucleus to form a triploid PEN. Since endosperm develops by mitosis in the triploid PEN it is also triploid.

1st PUC Biology Plant Kingdom Three Marks Diagram

Draw a neat labeled diagram.

Question 1.
1st PUC Biology Question Bank Chapter 3 Plant Kingdom 1

Question 2.

1st PUC Biology Question Bank Chapter 3 Plant Kingdom 2

Question 3.
1st PUC Biology Question Bank Chapter 3 Plant Kingdom 3

1st PUC Biology Plant Kingdom Five Marks Questions

Question 1.
Write the economic importance of algae.
Useful importances of algae are as following
(I) Food:

  • Chlorella contains proteins and vitamins A and D in abundant quantity.
  • Gelidium, Gracilaria, etc., produce ‘ agar-agar, a jelly-like substance used in baking, confectionary, for making cheese, jellies, ice cream etc.
  • Pottassium, sodium and chloride are found in the ionic form in seaweeds. These mineral contents are the unique supplement of balanced diet for humans.
  • Iodine are produced from brown seaweeds in Japan. However, in Russia, it is derived from red algae of Black sea.
  • Ulva Lactuca was used in Scotland for the preparation of a salad.
  • Used as the fodder of hens and milk cattle.

(II) In industry:

  • Diatoms develop into diatomaceous earth which is employed as filter for micro-organisms in sugar industry, in the manufacture of glass and porcelain, 3, varnish, polish and toothpaste.
  • Algin is used in vulcanization, typewriter roller, artificial fibres and to control blood flow during surgery.
  • Agar-Agar is used as base for a variety of cultural media.
  • Carageen possesses the property of gelling. Hence it is employed in the preparation of ice-cream and in the confectionery industry. It is also used in fruit jelly.
  • It is used in the manufacture of soaps and alums, prepared from seaweed ashes.

(III) In biological, nitrogen fixation:

  • Nostoc, Anabaena, etc., increase the fertility of soil.
  • Some algae are used as fertilizer and some blue-green algae are capable of converting clay soil into cultivable land.

(IV) Medicinal use:

  • An antibiotic Chlorellin is extracted from Chlorella.
  • Nitella causes the death of mosquitoes in ponds hence it is used in the control of malaria.

Question 2.
Write any eight characteristic of Pteridophyta.

  • Pteridophytes are vascular cryptogams They posses xylem and phloem tissues in their organs. They do not possess flowers and seeds.
  • The plant body is sporophyte differentiated into stem, root and leaves.
  • The leaves are sporophylls they bear spore-producing sporangia.
  • The sporophyte is diploid. It reproduces asexually and produces haploid spores.
  • The spores germinate and produce haploid gametophytes or prothallus. The gametophyte is independent and heart-shaped (In Nephrolepis).
  • Gametophyte is bisexual it consists of antheridia and archegonia (sex organs). They produce garnets by sexual reproduction.
  • Zygote or oospore is a resulting product of fertilization. It develops into the sporophyte.
  • In the lifecycle, there is an alternation of generation between diploid sporophyte and haploid gametophyte.

Question 3.
What are the common modes of reproduction in algae?
Reproduction in algae takes place by following methods :
(i) Vegetative reproduction – By this process, thallus divides into small fragments and each part, later on, gives rise to a new plant. This process is termed fragmentation.
(ii) Asexual reproduction It occurs by the formation of various types of spores in sporangia. Each spore is liberated from the mother cell and gives rise to a new plant. It generally takes place by the following spores:
(a) Zoospore: Under unfavourable conditions biciliated, tetraciliated (e.g., Ulothrix), or multiciliated. (e.g., Oedogonium) zoospores are formed.
(b) Aplanospores: The protoplasm gets separated from cell wall to form one or more, thin-walled, nonciliated aplanospores and each aplanospore gives rise to a new plant, e.g., Chlorella.
(c) Autospores: In some algae the resting spores develop into new plant inside the mother cell. These are also thin-walled and non-motile spores, e.g., Chlorococcus.
(d) Hypnospore: These are thick-walled non-motile spores formed to tide over unfavourable conditions e.g., Vaticheria
(e) Akinete: In this process entire cell becomes thick. Akinetes are formed under unfavourable conditions and on commencement of favourable conditions, each akinete develops into a new plant, e.g., Cladophora.
(f) Palmella stage: Under dry conditions, zoospores or aplanospores do not come outside the mother cell but get surrounded by a mucilaginous sheath. This is known as palmella stage. Under favourable conditions, they come out and give rise to a new plant, e.g., Chlamydomonas.
(g) Endospores: In most of the members of Myxophyceae, the development of a large number of endospores takes place inside the mother cell. Endospore gives rise to new plants under favourable conditions.
(h) Cysts: In some algae under unfavourable conditions and abundant food supply, the thallus divides into multinucleated and thick-walled smaller segments, which are termed ‘Cysts’. In favourable conditions, cysts give rise to new plants, e.g., Vaucheria.

Sexual Reproduction:

On the basis of behaviour, structure and nature of the gametes, sexual reproduction is of three types—
(a) Isogamous type: In some algae the gametes are similar in their external morphology and size. In this type (+) and (-) strain gametes fuse together to form zygospore, e.g., Chlamydomonas debaryanum and Ulothrix, Spirogyra.
(b) Anisogamous type: In some algae the gametes are similar in their external morphology but they differ in behaviour and size. The larger gamete is passive and it is known as macrogamete. The smaller gamete is active and it is known as microgamete. Their fusion give rise to zygote which later on undergoes reduction division to form new plants, e.g., Chlamydomonas braunii.
(c) Oogamous type: In this type of sexual reproduction fusion of small, biciliate or multiciliate and active male gamete with large non-ciliated and passive female gamete takes place and zygote is formed, e.g., Oedogonium, Fucus and Volvox.

KSEEB Solutions

Question 4.
Differentiate Dicot plants from Monocot Plants. (D.Kannada2011)

  • In dicots root system is a taproot.
    In monocots it is fibrous root system.
  • Leaves of dicots is shown reticulate venation.
    Leaves of monocots show parallel venation.
  • Seeds of dicots contain two cotyledons in their embryo
    Embryo has single cotyledon in monocots.
  • In dicots stele is Eustele.
    In monocots stele is atactostele.
  • In dicots flowers are tetra or pentamerous.
    In monocots flowers are trimerous.
  • Dicot plants undergo secondary growth.
    In monocots secondary growth is absent.
  • In dicots vascular bundles are open.
    In monocots vascular bundles are closed.
  • In dicots cambium is present.
    In monocots cambium is absent.

Question 5.
With a labelled sketch briefly explain fertilization In angiosperms. (D.Kannada., Tumkur, Hassan 2005)
Fertilization is the process by which fusion of the male and female gametes takes place. Fertilization involves pollen germination, entry of pollen tube into the embryo sac, release of male gametes anti-double fertilization. During pollen germination, the generative nucleus divides to form two male nuclei/gametes which are released into the embryo sac by the rupture of the pollen tube.

One of the gametes passes between the synergids and fuses with the egg cell to form the diploid zygote/oospore and the other fuses with the secondary nucleus to form the trlploldPEN/ primary endosperm nucleus. Since the male gamete participates in two fertilizations it is termed double fertilization and since the formation of the secondary nucleus is already a product of nuclear fusion it represents triple fusion.

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