CHSE Odisha Class 11 Biology Solutions Chapter 3 Classification of Plant Kingdom

Odisha State Board CHSE Odisha Class 11 Biology Solutions Chapter 3 Classification of Plant Kingdom Textbook Questions and Answers.

CHSE Odisha 11th Class Biology Chapter 3 Question Answer Classification of Plant Kingdom

Classification of Plant Kingdom Class 11 Questions and Answers CHSE Odisha

Very Short Answer Type Questions

Multiple choice type questions

Question 1.
Green algae possess
(a) chlorophyll-a, b
(b) chlorophyll-a, c
(c) chlorophyll-a, carotenes
(d) chlorophyll-6, carotenes
Answer:
(a) chlorophyll-a, b

Question 2.
Agar is obtained from
(a) Gelidium
(b) Riccia
(c) Spirogyra
(d) Laminaria
Answer:
(a) Gelidium

Question 3.
Colour of brown algae is due to
(a) carotenoids
(b) phycoerythrin
(c) phycocyanin
(d) fucoxanthin
Answer:
(d) fucoxanthin

Question 4.
The largest alga out of four of the following
(a) Spirogyra
(b) Fucus
(c) macrocystis
(d) Sargassum
Answer:
(c) macrocystis

Question 5.
The land plants that lack vascular tissue.
(a) Bryophyta
(b) Angiosperm
(c) Pteridophyta
(d) Cycads
Answer:
(a) Bryophyta

Question 6.
Sporophyte is fully dependent and parasitic on gametophytic body in
(a) bryophytes
(b) gymnosperms
(c) monocots
(d) dicots
Answer:
(a) bryophytes

Question 7.
Seedless vascular plants are the
(a) liverworts
(b) mosses
(c) ferns
(d) monocots
Answer:
(c) ferns

Question 8.
Multicellular branched rhizoids and leafy gametophytes are found in
(a) all pteridophytes
(b) bryophytes
(c) some pteridophytes
(d) gymnosperms
Answer:
(b) bryophytes

Question 9.
Smallest angiosperm is
(a) Striga
(b) Wolfia
(c) Eucalyptus
(d) Nicotiana
Answer:
(b) Wolfia

Question 10.
Which of the following algae is very rich in proteins?
(a) Ulothrix
(b) Chlorella
(c) Gelidium
(d) Oscillatoria
Answer:
(b) Chlorella

Question 11.
A seed plant having a palm-like habit is
(a) Pinus
(b) Gnetum
(c) Cycas
(d) Ginkgo
Answer:
(c) Cycas

Question 12.
Gymnosperms are characterised by
(a) small leaves
(b) fruits
(c) naked ovules
(d) ciliated sperms
Answer:
(c) naked ovules

Question 13.
The thallus of Riccia is
(a) triploid
(b) haploid
(c) diploid
(d) polyploid
Answer:
(b) haploid

Question 14.
Peat is formed by
(a) Riccia
(b) Anthoceros
(c) Sphagnum
(d) Funaria
Answer:
(c) Sphagnum

Question 15.
The sporophyte consisting of foot, seta and capsule is seen in
(a) Riccia
(b) Cycas
(c) Selaginella
(d) Funaria
Answer:
(d) Funaria

Choose the correct answer from the words given in bracket

Question 1.
One of the following is a vascular cryptogam.
(Bryophytes, Pteridophytes, Gymnosperms, Angiosperms)
Answer:
Pteridophytes

Question 2.
One of the following features of gymnosperms is seen among lower group of plants.
(Seed, Ovule, Archegonium, Nucellus)
Answer:
Archegonium

Question 3.
Haplontic life cycle pattern is seen in one of the following plant groups.
(Algae, Angiosperms, Gymnosperms, Bryophytes)
Answer:
Algae

Question 4.
In which of the following zygote does not give rise to embryo?
(Pteridophyte, Gymnosperms, Algae, Angiosperms)
Answer:
Algae

Question 5.
One of the following is a naked seeded plant.
(Angiosperms, Gymnosperms, Bryophytes, Algae)
Answer:
Gymnosperms

Fill in the blanks

Question 1.
Bog moss is a common name of …………. .
Answer:
Sphagnum

Question 2
………….. is the tallest angiosperms.
Answer:
Eucalyptus

Question 3.
Ferns contain underground stem called …………. .
Answer:
Rhizome

Question 4.
In red algae the reserved food is …………. .
Answer:
Floridean starch

Question 5.
The gymnosperms are ………… seeded plants
Answer:
Naked

Question 6.
The angiosperms are ………. seeded plants.
Answer:
Enclosed

Question 7.
Spirally arranged …………… constitute a cone.
Answer:
Micro and megasporophylls

Question 8.
Production of spores of different sizes is called ………….. .
Answer:
Heterospory

Question 9.
There is a single cotyledon in the embryo of …………. class of angiosperms.
Answer:
Monocotyledonous

Question 10.
Gametophytes and sporophytes are independent of each other in …………… .
Answer:
Pteridophytes

Short Answer Types Questions

Question 1.
Write notes on (explain briefly the following terms)
(i) Heter-ospory
(ii) Archegonium
(iii) Antheridium
(iv) Haplontic
(v) Diplontic
(vi) Sporophyll
(vii) Embryo sac
(viii) Isogamy
(ix) Double fertilisation
(x) Triple fusion
(xi) Protonema
Answer:
(i) Heterospory Phenomenon of producing spores of two different sizes.

(ii) Archegonium It is the female sex organ in bryophytes. It is a flask-shaped structure consisting of a basal venter containing egg and upper slightly elongated neck.

(iii) Antheridium It is the male sex organ in bryophytes which produces biflagellate antherozoids.

(iv) The dominant photosynthetic phase is a gametophyte produced by haploid spores. The gametophyte produces gametes by mitosis. The gametes fuse and produce a diploid zygote, that represents sporophytic generation. There sporophytes are dependent on gametophyte. Meiosis in the zygote results in formation of haploid spores. This kind of life cycle is called haplontic. Many algae such as Volvox, Spirogyra and Chlamydonwnas represent this pattern of life cycle. Plant life cycle Haplontic.

(v) Diplontio In this type, the diploid sporophyte is dominant. The multicellular diploid phase is called sporophyte. The gametophytic phase is represented by the single to few-celled haploid gametophyte. This kind of life cycle is termed as diplontic. All seed bearing plants, gymnosperms and angiosperms follow this pattern of life cycle. Fucus, an alga is diplontic.

(vi) Sporophyll These are spore bearing leaves in pteridophytes. In some cases they form distinct structures called strobilus (e.g. Selaginella) or compact cone (e.g. Equisetum).

(vii) Embryo sac Haploid cell containing structure in angiosperms. It consists of
(i) a three-celled egg apparatus,
(ii) three antipodal cells and
(iii) two polar nuclei.

(viii) Isogamylt is the process of fusion of similar gametes.

(ix) Double fertilisation In angiosperms, one male gamete fuses with the egg cell called syngamy to form a diploid zygote and other fuses with diploid secondary nucleus to form a triploid Primary Endosperm Nucleus (PEN). Because there are two fusions, this event is called double fertilisation.

(x) Triple fusion In angiosperm one of the male gamete fuses with diploid secondary nucleus to produce triploid primary endosperm nucleus.

(xi) Protonema Creeping, green, branched and frequently filamentous stage in bryophytes.

Differentiate between

Question 1.
Red algae and Brown algae
Answer:

Classes	Phaeophyceae	Rhodophyceae
Common Name	Brown algae	Red algae
Major pigments	Chlorophyll-a, c, fucoxanthin	Chlorophyli-a, d, phycoerythrin
Stored Food	Mannitol, Laminarin	Floridean starch
Cell Wall	Cellulose and algin	Cellulose, pectin and poly sulphate esters
Flagellar Number and Position of Insertions	2, unequal, lateral	Absent
Habitat	Fresh water (rare) brackish water, salt water (most)	Freshwater (some) brackish water, salt water (most)

Question 2.
Liverworts and Moss
Answer:

Liverworts	Mosses
They are dorsiventral.	They have radial symmetry,
Plants are thalloid or foliose.	Mosses are foliose.
Midrib is not present in leaves.	Leaves have unbranched midrib.
Rhizoids are unicellular and unbranched.	Rhizoids are multicellular and branched.
Plants bear scales.	Scales are absent in plants.
A conducting strand is absent.	A conducting strand is commonly present.
Sporophyte is differentiated in foot, seta and capsule.	It is not differentiated in foot, seta and capsule.
Capsule often possesses elaters.	Elaters are absent.
Dehiscence occurs through elaters.	Peristome performs this function.
A protonema stage is absent.	A juvenile protonema stage is present.

Question 3.
Bryophytes and Pteridophytes
Answer:

Bryophytes	Pteridophytes
The main plant body is gametophyte.	It is sporophyte.
These are non-vascular plants.	These are vascular plants.
Sporophyte is parasitic over gametophyte.	Sporophyte is independent of gametophyte.
Plant body can be thalius or foliose.	It is differentiated into stem, leaves and roots.
True stems and leaves are not present.	It has true stems and leaves.
Roots are absent, rhizoids are present.	Roots are present.
Sex organs are stalked.	Sex organs are sessile.
The wall of archegonial neck is 5-6 rowed.	The wall of archegonial neck is 4-rowed.

Question 4.
Syngamy and Triple fusion
Answer:

Syngamy	Triple fusion
Fusion of male one gamete with the egg cell.	Fusion of the one male gamete with diploid secondary nucleus.
It results in the formation of zygote(2n).	It results in the formation of triploid Primary Endosperm Nucleus(PEN) (3n).

Question 5.
Monocots and Dicots
Answer:

Monocots	Dicots
They contain one cotyledon.	They contain two cotyledons.
Leaves have parallel venation.	Leaves have reticulate venation.
Fibrous root system is present.	Tap root system is present.
Stomata are dumb-bell-shaped.	Stomata are kidney- shaped.
Vascular bundles are scattered.	Vascular bundles are arranged in rings.
Cambium Is absent.	Cambium is present.
Stems do not have concentric arrangement of tissue. A ground tissue is present.	Stems have concentric arrangement of tissue epidermis cortex, endodermis, pericycie, pith, etc.
Secondary growth is absent with some exception in stems.	These show secondary growth in stem.
Root has pith in its centre.	Root is generally devoid of pith.
Secondary growth is absent in roots with some exceptions.	Secondary growth occurs in roots.

Question 6.
Algae and Fungi
Answer:

Algae	Fungi
They are autotrophic.	They are heterotrophic.
Most forms are aquatic.	Most forms are terrestrial.
Cell wall is made up of cellulose.	Cell wall is made up of chitin.
Contain starch as stored food material.	Contain glycogen and oils as stored food material.

Long Answer Type Questions

Question 1.
Describe the basis of classification and general characters of algae.
Answer:
Classification of Algae
Algae are divided into various classes based on pigmentation, type of stored food materials and kind of flagellation. The three main classes are Chlorophyceae, Phaeophyceae and Rhodophyceae.

1. Class-Chlorophyceae (Green Algae)
The members of Chlorophyceae are commonly called green algae. There are about 7000 species in this class.
The reserve food material is starch.
The characteristic features of Chlorophyceae are discussed below
(i) Habitat These are mostly marine forms, only some are freshwater. Chlorella can tolerate moderately warm waters. Snow dwelling forms are called cryophytes, e.g. Chlamydomonas nivalis, Scotiella, etc.

(ii) Cell Organisation Cell walls contain cellulose (inner layer) and pectose (outer layer) in most of the green algae. The chloroplasts may be discoid, plate-like, reticulate, cup-shaped, spiral or ribbon-shaped.
The chloroplasts contain photosynthetic pigments chlorophyll- a and b. Most of the members have one or more storage bodies called pyrenoids located in the chloroplasts. Pyrenoids contain protein besides starch.
Some algae may store food in the form of oil droplets also.

(iii) Thallus These are unicellular, colonial, coenocytic and multicellular forms. Unicellular green algae can be flagellate, (Chlamydomonas) or non-flagellate (Chlorella). Acetabularia (umbrella plant) has a single cell upto 10 cm long with distinction of nucleus containing rhizoid, elongated stalk and umbrella-like cap.
A colony for fixed number of individual cells (Volvox) is called coenobium. Coenocytic or siphonaceous thallus occurs in Caulerpa. Unbranched filamentous thallus in Ulothrix, Spirogyra heterotrichous in Stigeoclonium and parenchymatous in Ulva.

(iv) Reproduction The members of Chlorophyceae reproduce vegetatively, asexually and sexually by various methods. Vegetative reproduction occurs through cell division (unicellular forms), fragmentation, stolons, tubers, storage cells, etc. Asexual reproduction occurs by zoospores, aplanospores, hypnospores, akinetes and daughters colonies. Sexual reproduction may be isogamous, anisogamous or oogamous.

(v) Life Cycle It can be haplontic (e.g. Spirogyrai) diplontic (e.g. Cladophora) and haplodiplontic (e.g. Ulva)

2. Class-Phaeophyceae (Brown Algae):
The members of Phaeophyceae contain fucoxanthin pigment and include phycocolloid rich multicellular eukaryotic algae. Its common members are seaweeds called kelps. This class is comprised of about 2000 species.
(i) Habitat Brown algae are mostly marine. These are found mostly in colder seas or during cold seasons in tropical regions.

(ii) Size They range from simple branched, filamentous forms (Ectocarpus) to profusely branched forms as represented by kelps (Macrocystis).
These represent some of the largest algae, i.e. Macrocystis (40-100 m) and Nereocystis (20-30 m).

(iii) Cell Organisation All members are multicellular. Cell wall is composed of cellulose, pectose and phycocolloids. The cellulosic wall of vegetative cells is usually covered on the outside by a gelatinous coating of algin.

Brown algae (Phaeophyceae)

(iv) Thallus It is heterotrichous filament with both prostrate and upright branches (Ectocarpus). The parenchymatous structure is found in higher forms. The plant body of large forms often differentiated into holdfast (it usually attaches to the substratum) a stalk called the stipe and lamina (frond), which is photosynthetic. Conducting tubes or trumpet hyphae are present in larger brown algae or kelps. They help in conduction of food materials.

(v) Photosynthetic Pigments and Colour These include chlorophyll-a, c and carotenoids. They range in colour from olive green to various shades of brown depending upon the amount of the xanthophyll and fucoxanthin present in them.

(vi) Food Reserve It remains in the form of complex carbohydrates such as laminarin or mannitol.

(vii) Flagellation These contain heterokont flagellation with one smooth (whiplash) and other one tinsel flagella.

(viii) Reproduction Vegetative reproduction occurs through fragmentation (e.g. Sargassum), adventitious branches and stolons (e.g. Dictyotd).
Asexual reproduction by biflagellate zoospores, which are pear-shaped having two unequal laterally attached flagella.
Sexual reproduction occurs by isogamy, anisogamy and oogamy. Union of gametes may take place in water or within the oogonium (oogamous species). The gametes are pyriform (pear-shaped) and have two laterally attached flagella. ,

(ix) Life Cycle Isomorphic alternation of generations is found in some brown algae, e.g. Ectocarpus,
Dictyota. In many brown algae, the diploid , generation or phase is dominant. The haploid phase is either microscopic or represented by gametes only (e.g. Fucus).

Question 2.
Name plant group which bears archegonia and describe the characteristic features of first archegoniate land plant.
Answer:
Archegonia is found in bryophytes.
Bryophytes:
These include the various mosses and liverworts. These are non-vascular embryophytes, characterised by the presence of an independent gametophyte and parasitic sporophyte.
1. Habitat
Bryophytes commonly grow in moist, shaded areas in hills. These are also called amphibians of the plant kingdom because, these can live in soil, but are dependent on water for sexual reproduction.
Some bryophytes grow in diverse habitats, such as

• Aquatic, e.g. Riccia fluitans, Ricciocarpus, Riella
• Epiphyte, e.g. Radula, Dendroceros
• Saprophyte, e.g. Buxbaumia, Cryptothallus
• Dry habitats, e.g. Polytrichum
• Deserts, e.g. Tortula desertorum
• Dry rocks, e.g. Porella

2. Thallus Organisation
The plant body of bryophytes is more differentiated than that of algae. It is thallus-like, prostrate, erect and remain attached to the substratum by unicellular or multicellular rhizoids. Root, stem and leaves are not present on thallus.

3. Sex Organs
The main plant body is haploid that produces gametes, hence, it is called gametophyte. The sex organs in bryophytes are multicellular, the male sex organs in bryophytes is called antheridium (which produces biflagellate antherozoids) and the flask-shaped female sex organ is called archegonium (produces a single egg).

4. Reproduction
Sexual type of reproduction is common. The antherozoids are released into water where they come in contact with archegonium.

• Fertilisation It occurs inside the archegonium. The egg secretes a chemical which attracts spermatozoids. Sperms require a thin film of water for swimming and reaching the dehisced archegonium. One sperm fuses with an egg and produces a diploid zygote. Zygotes do not undergo reduction division immediately instead, they produce a multicellular body called sporophyte.
• Dependent Sporophyte The sporophyte is not free-living, it remains attached to the photosynthetic gametophyte for nourishment. Some cells of the sporophyte undergo reduction division (meiosis) to produce haploid spores. These spores germinate to produce gametophyte.
• Sporogonium The sporophyte of bryophytes is also called sporogonium because it is dependent on the gametophyte and is meant for producing spores.

5. Life Cycle
Bryophytes have heteromorphic alternation of generations. The gametophyte may be produced directly or through a first formed juvenile stage called protonema.

Antheridum, archegonium and lifecycle of Funaria (Moss) showing alternation of generations

Economic importance of Bryophytes:
Bryophytes in general are of little economic importance. But, several species have some uses.

1. Some mosses provide food for herbaceous mammals, birds and other animals.
2. Species of Sphagnum (a moss), provides peat that have long been used as fuel. It has the capacity to hold water as packing material for transshipment of living materials.
3. Mosses along with lichens are the first organisms to colonise rocks. Hence, these help in biological succession. They decompose rocks making the substrate suitable for the growth of higher plants.
4. Mosses form dense mats on the soil. They reduce the impact of falling raindrops and thus, prevent soil erosion.
5. Marchantia has medicinal properties to cure lungs and liver infections. It also has anti-tumour properties.

Question 3.
If both gymnosperms and angiosperms bear seeds, then why they are classified separately?
Answer:
Gymnosperms and angiosperms are classified separately although they both bear seeds because of following reason
(i) Ovules in gymnosperms are naked. In angiosperms, they are enclosed inside the ovary.
(ii) Wood is non-porous is gymnosperm, i.e. the vessels are absent.

Gymnosperms	Angiosperms
Megasporophylls are woody and there is no rolling of megasporophylls.	Magasporophylls are softer and rolled into ovary, style and stigma.
Ovules are exposed.	Ovules are enclosed in ovary.
Archegonia is present.	Archegonia is absent.
Pollen enters micropyle directly.	Pollen germinates on stigma, pollen tube passes through style to enter ovary.
Single fertilisation.	Double fertilisation
Endosperm is haploid and formed before fertilisation.	Endosperm is triploid and formed after fertilisation.
Seeds are exposed because there in no ovary, so no fruit formation.	Seeds are enclosed in a fruit which are formed after fertilisation.

Question 4.
What are gymnosperms? Describe their economic importance.
Answer:
The gymnosperms (Gymnos – naked; sperma – seeds) are plants in which the ovules are not enclosed by any ovary wall and remain exposed, both before and after fertilisation. These are small groups of seed plants which are represented by only 900 living species. Unlike bryophytes and pteridophytes, in gymnosperms, the male and the female gametophytes do not have an independent free-living existence. They remain within the sporangia retained on the sporophytes.

Economic Importance of Gymnosperms:

1. Seeds of Pinus gerardiana (chilgoza) are used as food after roasting. Some other edible gymnosperm plant parts are endosperm of Ginkgo, seed kernel of some Cycas and Gnetum, sago grains from stems of Cycas, etc.
2. Gymnosperms provide softwood for construction, plywood and paper industry.
3. Branches of gymnosperm trees are used as fuel.
4. Saw dust of conifers is used in making plastics and linoleum.
5. Resin is a semifluid secreted by special tubes of a number of conifers. It helps in sealing female cones after pollination, scale leaves around leaf bases and apical buds. Resin is distilled to obtain turpentine and resin. Turpentine is used for thinning paints, varnishes, etc., and resin is used for sealing joints of wheel, preparation of writing paper, oil, clothes, etc.
6. Ephedrine an antibiotic is obtained from Ephedra. It is used for curing respiratory problems and asthma.
7. Taxol is an anticancer drug obtained from Taxus.