Each plant or group of plants has some phylogenetic significance in relation to evolution. Cycas, one of the few living members of gymnosperms is called as 'relic of the past". Can you establish a phylogenetic relationship of Cycas with any other group of plants that justifies the above statement.
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Each plant or group of plants has some phylogenetic significance in relation to evolution. Cycas, one of the few living members of gymnosperms is called as 'relic of the past". Can you establish a phylogenetic relationship of Cycas with any other group of plants that justifies the above statement.
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Cycas is called the ‘relic of the past.’
It has following
properties to justify this
(i) Monoxylic wood through secondary growth started
(ii) Shedding of seed when embryo is still immature.
(iii) Arrangement of microsporangia in all defined sori.
Phylogenetically, Cycas is related to pteridosperms (sed
ferns) and through them to ferns from which it seems to
have evolved. It can be ascertained by the presence Of
(i) leaf-like megasporophyll
(ii) persistence of leaf bases.