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Tag Archives: angiosperm

Discovery about the Male, Female Gametophytes & Syngamy

Among early students of the development of pollen, Hofmeister (1848) presented some surprisingly good illustrations of the process of tetrad formation (microspore tetrad), and Reichenbach, Hartig and several other workers noted the presence of two nuclei in whole mounts of the mature pollen grains of several angiosperms. Discovery of nature …

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Chemotaxonomy: Semantides

Semantides are information-carrying molecules. Semantides provide taxonomic data not on the basis of presence or absence, but in terms of sequences, ratios or percentages,. Semantides are of three types, viz., Primary semantide – DNA Secondary semantide- RNA Tertiary semantides – Proteins Sometimes the semantides together with the larger polysachharides, are …

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Biosystematics: Steps and Categories

The steps in the biosystematic investigation are as follows A sampling of taxon and its population and cytological study of the chromosome of many populations within geographical races, species, and genera; differences in chromosome number, morphology, and behavior of meiosis indicated genetic differences. Determination of the ability of the different …

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