Plant Kingdom: Class 11 Biology NCERT Chapter 3
Key Features of NCERT Material for Class 11 Biology Chapter 3 – Plant Kingdom
In the previous chapter: Biological Classification, you must have studied the procedure of grouping together different organisms according to their identities, dissimilarities, and phylogenetic. Now, in chapter 3 of your class 11 Biology NCERT textbook: the Plant Kingdom, you will study Plant kingdom including algae, bryophytes, pteridophytes, gymnosperms and angiosperms.
Wherever you see, you see a green spread, with various sorts of plants and trees. Plants and plant items are something extremely recognizable that you use in your regular day to day existence. Be that as it may, have you at any point pondered about the various sorts of plants and trees? Did you realize that the Plant Kingdom is isolated into a few subgroups, with everyone having extraordinary highlights? Dig into the profundities of Kingdom Plantae and uncover a portion of the intriguing realities.
In light of whether plants have a very much separated body and the nearness or nonattendance of particular tissues for transport, and the capacity to hold up under seeds Kingdom Plantae (Plant Kingdom) can be grouped into various divisions. The highlights and instances of every division are referenced hereunder.
Division Thallophyta
These are the lowermost plants of the plant realm, without an all around separated body structure. This implies the plant body isn’t separated as roots, stem, and leaves. They are usually called green growth, and are forever oceanic. Models incorporate Spirogyra, Chara, and Ulothrix.
Quick revision notes
- Eukaryotic, multicellular, containing chlorophyll and having cell divider, are assembled under the domain Plantae. It is noticeably known as plant domain.
- Phylogenetic arrangement of characterization dependent on developmental relationship is utilized for ordering plants.
- Numerical Taxonomy uses a PC by appointing code for each character and breaking down the highlights.
- Cytotaxonomy is based on cytological data like chromosome number, structure and conduct.
- Chemotaxonomy utilizes concoction constituents of plants to determine the disarray.
Algae: These incorporate the least difficult plants which have undifferentiated or thallus like structures, conceptive organs single celled called gametangia. It incorporates just Algae.
Characteristics of Algae
- Plant body is thallus, which might be unicellular, provincial, filamentous or parenchymatous.
- Normally amphibians however a couple are likewise found in clammy earthbound territories like tree trunks, wet rocks, damp soil, and so on.
- Vascular tissues and mechanical tissues are missing.
- Expansion is vegetative by crack, asexual by spore course of action (zoospores) and sexual engendering by mix of two gametes which may have been Isogamous (Spirogyra), Oogamous (Volvox) or Anisogamous (Chlamydomonas).
- Life cycle is different haplontic, diplontic or diplohaplontic.
| Green Algae | Brown Algae | Red Algae |
| Mostly fresh water and sub aerial. | Mostly marine. | Mostly marine. |
| Unicellular organisms are abundant. | Unicellular species are absent. | Unicellular species are fewer. |
| Chlorophyll a and b type. | Chlorophyll a and c type. | Chlorophyll a and d type. |
| Reserve food is starch | Reserve food is laminarin. | Reserve food is floridean starch. |
| Cell wall is cellulose. | Cell wall contains cellulose and algin. | Cell wall contains cellulose and poly-sulphate esters. |
| Fucoxanthin is absent | Fucoxanthin present. | Phycoerythrin is present. |
| Zoospores present. | Zoospores present. | Zoospores absent. |
| Chlamydomonas, Ulothrix, spirogyra. | Focus, Sargassum, ectocarpus. | Polysiphonia, Gelidium, Porphyra etc. |
Economic importance-
- Various earthy colored green growth ( Laminaria, Sargassum) are utilized as food in certain nations.
- Fucus and Laminaria are affluent sources of Iodine.
- Laminaria and Ascophyllum have anti-toxin properties.
- Alginic corrosive is acquired from Fucus and Sargassum, which is utilized as emulsions.
Bryophytes
They are non-vascular greeneries and liverworts that develop in sodden obscure districts. They are called creatures of land and water of plants on the grounds that these plants live on soil however reliant on water for sexual multiplication.
Characteristic features
- Live in sodden and obscure living spaces, found to develop during stormy seasons on soggy soil, rocks, dividers, and so forth.
- The prevailing stage or plant body is free living gametophyte.
- Roots are missing yet contain rhizoids
- Vegetative generation is by discontinuity, tubers, gemmae, buds and so on sex organs are multicellular and jacketed. The male sex organ is called antheridium. They produce biflagellate antherozoids. The female sex organ called archegonium is jar formed and creates a solitary egg.
- Sporophyte is reliant on gametophyte for sustenance.
Bryophytes Hepaticopsida (Liverworts)
- The plant part of the body of a liverwort is thalloid, e.g., Marchantia. The thallus is dorsive and apperessed to the substrate.
- Abiogenetic propagation in liverworts happens by discontinuity, or by the development of specific structures called gemmae.
- Gemmae are green, multicellular, asexual buds, which are created in little containers called gemma cups. The gemmae gets isolated from the parent body and grow to frame new people
- During sexual generation, male and female sex organs are delivered either on the equivalent or on various thalli. The sporophyte is separated into a foot, seta and case. Spores delivered inside the container develop to frame
- free-living gametophytes.
Bryopsida (Mosses)
- The gametophyte of greeneries comprises two phases the main stage is the protonema stage, which grows straightforwardly from spores. It is crawling, green and much of the time filamentous. The subsequent stage is the verdant stage, which creates from secondary protonema as sidelong buds having upstanding, thin tomahawks bearing spirally organized leaves.
- Vegetative propagation is by the fracture and growing in optional protonema. In sexual generation, the sex organs antheridia and archegonia are created at the summit of the verdant shoots.
- Sporophytes in greeneries are more evolved and comprise of foot, seta and case.
- Regular models are Funaria, Polytrichum, Sphagnum and so forth.
Pteridophytes
- They are seedless vascular plants that have sporophytic plant bodies and subtle gametophytes. Sporophytic plant body is separated into genuine stem, roots and leaves.
- Vascular tissue is available yet vessels are missing from xylem and friend cells and sieve tubes are missing.
- Sporophytes bears sporangia that are subtended by leaf-like far points called sporophylls. In specific plants (Selaginella) a limited structure called strobili or cone is molded.
- Sporangia bears spores by meiosis in spore mother cells. Spores develop to convey multicellular thalloid, prothallus.
- Gametophyte bears female and male sex organ called archegonia and antheridia. Water is required for planning of male and female gametes.
- The greater part of Pteridophytes produce spores of comparative kind (homosporous) yet in Selaginella and Salvinia, spores are of two sorts (heterosporous) bigger considered megaspore that produce female gametophyte and littler microspore that produce male gametes.
Gymnosperms:
- Gymnosperms are those plants where the ovules are not encased inside the ovary divider and stay uncovered when preparation.
- They are enduring and woody, shaping either shrubs or trees. Some are extremely enormous (Sequoia sempervirens) and others are exceptionally little (Zamia pygmaea).
- Stems might be unbranched(Cycas) or branched(Pinus). Root is taproot. Leaves might be straightforward or compound.
- They are heterosporous, produce haploid microspore and megaspore in male and female Strobili individually.
- Male and female gametophytes don’t have autonomous free-living presence. Fertilization happens through air and zygote forms into undeveloped organisms and ovules into seeds. These seeds are stripped.
- Model Pines, Cycus, Cedrus, Ginkgo, and so forth.
Angiosperms
- Dust grains and ovules are created in a particular structure called bloom. Seeds are encased inside the organic products.
- Size changes from practically tiny Wolffia (0.1cm)to tall tree Eucalyptus (more than 100m
- The male sex organs in a bloom is the stamen. It contains dust grain.
- The female sex organs in a bloom is the pistil or the carpel. Pistil comprises an ovary walling one in or numerous ovules. Inside ovules are available exceptionally decreased female gametophytes named embryo sacs.
- All the embryo sacs have a three-celled egg contraption – one egg cell and two synergids, three antipodal cells and two polar cores. The polar cores in the end breaker to create a diploid secondary nucleus.
Angiosperms are further classified into:
- Monocotyledons
- Dicotyledons
| Monocotyledons | Dicotyledons |
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- Twofold treatment Each dust grain produces two male gametes. One gametes intertwine with an egg to shape an embryo. This is called Syngamy. Different gametes intertwine with two polar cores to shape endosperm, triple combination. Since fertilization happens twice, it is called double fertilization .
Alternation of generation
Distinctive plant bunches total their life cycles in various examples. Angiosperms complete their life cycle in two stages: diploid sporophytes and haploid gametophyte. The two follow one another. This is called alternation of generation.
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- Haplontic-Saprophytic age is spoken to by just the one-celled zygote. Meiosis in zygote results into haploid spores to shape gametophytes, which is the prevailing vegetative stage. Model Volvox, Spirogyra and so forth.
- Diplontic-Diploid sporophytes are predominant, free, photosynthetic plants. The gametophyte is spoken to by single to not many celled people. All seed bearing plants fall under this classification.
- Haplo-diplontic- Both are multicellular and a condition is present. It is also present in Pteridophytes and Bryophytes.