Plant Kingdom NCERT Flash Card

  • Artificial system of classification involves usage of one or few morphological characters.

  • Phylogenetic system plays important role in elucidation of​​ evolutionary relationships.

  • DNA sequence is the basis of grouping organisms in​​ ​​ Chemotaxonomy

  • Chemotaxonomy involves grouping of organisms on the basis of :

    • DNA sequence

    • RNA sequence

    • Chemical nature of protein etc.

 

(Algae)

 

  • Plants which are not differentiated into roots, stems and leaves are​​ Algae,​​ Algae are thallophytes.

  • Cell wall of Spirogyra is composed​​ of pectin and cellulose.

  • Kelps are massive brown algae.

  • Laminarin​​ is the stored food in brown algae e.g., Dictyota.

  • Sexual reproduction in​​ red algae​​ is​​ oogamous e.g., Gracilaria, Gelidium

  • Ectocarpus is branched filamentous brown algae

  • Carrageen – Red algae

  • Algin – Brown algae

  • Agar – Red algae

  • Single celled protein – Spirullina

  • Photosynthetic pigments in algae are present in chloroplast.

 

(Bryophytes)

 

  • They are dependent on water for sexual reproduction

  • They usually occur in damp, humid and shaded localities

  • They play an important role in plant succession on bare rocks

  • The main plant body in bryophytes​​ is haploid.

  • Peat is obtained from​​ Sphagnum.

  • Liverworts reproduce asexually by​​ gemmae​​ and fragmentation.

  • Sphagnum is used for transportation of seedling of cut plants.

  • In mosses the sex organs are present in the leafy stage.

  • Antherozoids​​ represent male motile gametes.

 

(Pteridophytes)

 

  • In pteridophytes, spores germinate to give rise​​ prothallus.

  • In Selaginella the embryo develops into sporophyte.

  • In pteridophytes, the megaspore germinates to form female gametophytes.

  • Young embryos of pteridophytes within the female gametophyte – precursor to the seed habit.

  • Pteridophytes possess vascular tissues but lacks seeds. e.g., Ferns

  • In pteridophytes, gymnosperm and angiosperm ;​​ The main plant body is sporophytes differentiated​​ into true root, stem and leaves.

  • Pteridophytes,​​ first terrestrial plants​​ to possess​​ vascular tissues.

  • In pteridophytes, fusion of gametes takes place in​​ archegonium.

 

(Gymnosperms)

 

  • Gymnosperms are​​ first seeded plants.

  • Gymnosperms​​ have tap root system.

  • Pinus​​ has both the male and female cones on same plant body​​ Pinus is monoecious.

  • Gymnosperms​​ possess ​​ (Naked seeds)

  • Coralloid​​ roots have a symbiotic association with Nitrogen-fixing cyanobacteria.

  • The megaspore mother cell is differentiated from one of the cells of the​​ Nucellus

  • The cones bearing microsporophylls are known as​​ Male strobili.

  • Pollen grains are released from microsporangium.

 

 

(Angiosperms)

 

 

  • In angiosperms the sporophylls are organised into flowers.

  • Wolfia is a microscopic angiosperm.

  • Endosperm of angiosperm is triploid (3n).

  • Fusion of a male gamete with the secondary nucleus forms the​​ Endosperm

  • Triple fusion – Fusion of a male gamete with secondary nucleus

  • In angiosperms, female gametophyte is also known as embryo sac.

  • Double fertilization​​ is an event unique​​ to angiosperms.

  • Stigma​​ functions as landing platform for the pollen grains in flowering plants.

  • Cells of embryo sac degenerate after fertilisation in angiosperms these are synergids and antipodal cells.

  • In angiosperms,​​ the megasopre​​ develops into embryo sac.

  • The germination of pollen grain results in the formation of pollen tube.

  • Cotyledons are embryonic leaves.

 

Haplo-diplontic condition is exhibited by​​ Bryophytes

Haplontic life cycle is represented by​​ Volvox

Fucus​​ exhibits diplontic life cycle

 

 

 

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