NEET Biology : Plant kingdom One short notes 2027 Class 11 Chapter 3

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Dropping Complete Notes of Ch-3 Plant Kingdom for NEET 2027 Aspirants 🌱

Algae to Angiosperms + PYQ Hotspots included!

NEET 2027: Chapter 3 Plant Kingdom - Complete Short Notes* 🌱  

_Class 11 Biology | NCERT + PYQ Hotspots | 3-4Q Fix Aate Hain_  

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### *1. Classification Systems*  

1. *Artificial System*: Linnaeus. Based on 1-2 vegetative characters = Androecium structure. Easy but not natural.  

2. *Natural System*: Bentham & Hooker. Based on natural affinities, morphology, anatomy.  

3. *Phylogenetic System*: Engler & Prantl. Based on evolutionary relationships. Hutchison, Takhtajan also gave.  

4. *Numerical Taxonomy*: Computers. Uses all observable characters. Each character given number & code.  

5. *Cytotaxonomy*: Chromosome number, structure, behavior.  

6. *Chemotaxonomy*: Chemical constituents of plants.  

### *2. Algae* `1Q Pakka`  

- *Habitat*: Mostly aquatic. Fresh + Marine.  

- *Thallus*: Simple, no tissue differentiation.  

- *Reproduction*:  

    1. *Vegetative*: Fragmentation.  

    2. *Asexual*: Zoospores = flagellated, Aplanospores = non-motile.  

    3. *Sexual*: Isogamy, Anisogamy, Oogamy.  

*Classes of Algae*:

**Feature** **Chlorophyceae** **Phaeophyceae** **Rhodophyceae**

**Common Name** Green algae Brown algae Red algae

**Pigment** Chl a, b Chl a, c + Fucoxanthin Chl a, d + Phycoerythrin

**Stored Food** Starch Laminarin + Mannitol Floridean starch

**Cell Wall** Cellulose Cellulose + Algin Cellulose + Pectin + Poly sulphate esters

**Flagella** 2-8, equal, apical 2, unequal, lateral Absent

**Habitat** Fresh water Marine Marine, deeper water

**Examples** *Chlamydomonas*, *Volvox*, *Ulothrix*, *Spirogyra*, *Chara* *Ectocarpus*, *Dictyota*, *Laminaria*, *Sargassum*, *Fucus* *Polysiphonia*, *Porphyra*, *Gracilaria*, *Gelidium*

*NEET Gold*:  

1. *Hydrocolloids*: Algin = Brown algae. Carrageen = Red algae. Used in ice-cream, jellies.  

2. *Agar*: From _Gelidium_ & _Gracilaria_. Used to grow microbes, ice-cream.  

3. *Protein rich*: _Spirulina_ = Single cell protein = SCP.  

### *3. Bryophytes* `Amphibians of Plant Kingdom`  

- *Habitat*: Damp, humid, shaded places. Need water for fertilization.  

- *Main Plant Body*: Gametophyte = Haploid, dominant, independent, photosynthetic.  

- *Sporophyte*: Diploid, dependent on gametophyte for nutrition.  

- *No Vascular Tissue*: No xylem & phloem. No true roots, stem, leaves. Rhizoids present.  

- *Sex Organs*: Antheridium = Male. Archegonium = Female = Flask shaped.  

*Classes*:  

1. *Liverworts*: _Marchantia_, _Riccia_. Thalloid body. Asexual by gemmae in gemma cups.  

2. *Mosses*: _Funaria_, _Polytrichum_, _Sphagnum_.  

      - *Gametophyte*: 2 stages = Protonema = Juvenile, Creeping. Leafy stage = Adult.  

      - *Sporophyte*: Foot + Seta + Capsule.  

      - *NEET Point*: _Sphagnum_ = Peat moss. Used as fuel, packing material. Holds water.  

### *4. Pteridophytes* `First Terrestrial Plants with Vascular Tissue`  

- *Main Plant Body*: Sporophyte = Diploid, dominant, independent. Has true root, stem, leaves.  

- *Vascular Tissue*: Xylem & Phloem present.  

- *Leaves*: Small = Microphylls in _Selaginella_. Large = Megaphylls in Ferns.  

- *Reproduction*: Spores in sporangia. Sporophylls form strobili/cones in _Selaginella_, _Equisetum_.  

- *Gametophyte*: Prothallus = Small, inconspicuous, independent, photosynthetic. Needs water for fertilization.

**Type** **Spore** **Example**

**Homosporous** 1 kind of spore *Pteris*, *Dryopteris*, *Adiantum*

**Heterosporous** 2 kinds = Micro & Megaspore *Selaginella*, *Salvinia*

*NEET Gold*: Heterospory = Origin of seed habit. _Selaginella_ & _Salvinia_ are heterosporous.  

### *5. Gymnosperms* `Naked Seeds`  

- *Meaning*: Gymno = Naked, Sperma = Seed. Ovules not enclosed by ovary.  

- *Plant Body*: Sporophyte dominant. Vascular tissue present.  

- *Roots*: Tap roots. _Pinus_ = Mycorrhiza. _Cycas_ = Coralloid roots + Cyanobacteria = N₂ fixation.  

- *Stem*: Branched = _Pinus_, _Cedrus_. Unbranched = _Cycas_.  

- *Leaves*: Needle-like = _Pinus_ to reduce transpiration. Pinnate = _Cycas_.  

- *Reproduction*: Heterosporous. Male cone + Female cone. Pollination = Wind. Fertilization = Siphonogamy.  

- *Examples*: _Cycas_, _Pinus_, _Ginkgo_, _Cedrus_, _Sequoia_ = Tallest tree.  

*NEET Point*: _Cycas_ = Dioecious. Male cone & female cone on different plants. _Pinus_ = Monoecious.  

### *6. Angiosperms* `Flowering Plants`  

- *Seeds Enclosed*: In fruit = Ovary develops into fruit.  

- *Most Advanced*: 2 Classes = Dicots & Monocots.  

- *Double Fertilization*: Unique. Syngamy + Triple fusion → Embryo + Endosperm.  

- *Male Sex Organ*: Stamen. Female = Pistil.

**Feature** **Dicot** **Monocot**

**Cotyledons** 2 1

**Venation** Reticulate Parallel

**Roots** Tap root Fibrous root

**Floral Parts** 4-5 or multiples 3 or multiples

**Vascular Bundle** Ring, Cambium present Scattered, Cambium absent

**Example** Mango, Pea, Sunflower Wheat, Maize, Grass

### *7. Plant Life Cycles & Alternation of Generations*  

1. *Haplontic*: Dominant gametophyte = n. Zygote = only diploid. Meiosis in zygote = Zygotic meiosis. Ex: _Volvox_, _Spirogyra_, _Chlamydomonas_.  

2. *Diplontic*: Dominant sporophyte = 2n. Gametophyte = few celled. Meiosis in gamete formation = Gametic meiosis. Ex: _Fucus_, Gymnosperms, Angiosperms.  

3. *Haplo-diplontic*: Both phases multicellular. Sporic meiosis. Ex: _Ectocarpus_, _Polysiphonia_, Bryophytes, Pteridophytes.  

### *8. Last 5 Year PYQ One Liners* `Ratta Maar Le`  

1. *Agar* = From _Gelidium_ & _Gracilaria_ = Red algae = NEET 2024, 2020.  

2. *Heterospory* = _Selaginella_ & _Salvinia_ = Origin of seed habit = NEET 2023, 2019.  

3. *Protonema* = Juvenile stage in Moss = NEET 2022.  

4. *Coralloid roots* = _Cycas_ + Cyanobacteria = N₂ fixation = NEET 2021.  

5. *Gemmae* = Asexual reproduction in _Marchantia_ liverwort = NEET 2020.  

6. *Fucoxanthin* = Brown algae pigment = NEET 2019.  

7. *Diplontic life cycle* = _Fucus_ brown algae, Gymnosperms, Angiosperms = NEET 2023.  

8. *Floridean starch* = Stored food in Red algae = NEET 2018.  

9. *Pollution indicator* = Lichens not algae, but _Sphagnum_ moss holds water = NEET 2017.  

10. *Tallest tree* = _Sequoia_ = Gymnosperm = NEET 2016.