Q. Refer to the given flow chart regarding different groups of Kingdom Plantae.
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Which of the following is true regarding P, Q, R, S and T ?

 1954  232 Plant Kingdom Report Error

Solution:

Cryptogams are the plants without seeds. In the given flow chart, 'P' represents algae in which sex organs are usually unicellular and non-jacketed. 'Q′ represents pteridophytes, in which both sporophytic and gametophytic generations are independent. In pteridophytes, the main plant body is sporophyte which is differentiated into true root, stem and leaves. 'R' represents bryophytes in which diploid sporophyte lives as a parasite on an independent haploid gametophyte. All known members of bryophytes have been found to be homosporous. 'S' and 'T' respectively represent angiosperms and gymnosperms, which are included under phanerogams. Gymnosperms evolved earlier and thus are more ancient than angiosperms. Gymnosperms formed dominant flora on Earth about 200 million years ago in the mesozoic era.