Plant Kingdom

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DÏÇØTS

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Seeds having two cotyledon

Eg. Mustard, Pea, Beans

MØÑØÇØTS

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Seeds having only one cotyledon

Eg. Grasses, wheat, Rice

PLÅÑT LÏFË ÇÝÇLËS ÅÑD ÅLTËRÑÅTÏØÑ ØF GËÑËRÅTÏØÑS

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Plants cells divide by mitosis to grow and

produce different plant bodies like haploid

and diploid. Haploid plant bodies are called

gametophyte and diploid plant bodies are

called sporophyte.

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Sexually

reproducing

plants

exhibit

alternation

of

generations

between

gametophyte (n) and sporophyte (2n) in a

complete life cycle.

PÅTTËRÑS ØF PLÅÑT LÏFË ÇÝÇLËS

HÅPLØÑTÏÇ LÏFË ÇÝÇLË

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Gametophyte

generation

–

dominant;

photosynthetic and free-living.

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In sporophytic generation, there is only one-

celled zygote which is not free-living and

undergoes meiosis to form spores that divide

mitotically to produce new gametophyte

Examples: Volvox and Spirogyra and some

species of Chlamydomonas.

Gametophyte (n)

Divides by mitosis

Gametes (n)

Fertilisation

Zygote (2n)

Divides by mitosis

Sporophyte (2n)

Divides by meiosis

Spores (n)

Divide by mitosis again

New gametophyte (n)