Pinus: Salient Features, Morphology and Reproduction

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Pinus are coniferous, evergreen resinous trees which are popularly known as pine. They belong to the family Pinaceae under order Coniferales of class Coiniferosida. Different species of the genus Pinus are distributed throughout the temperate and sub-alpine regions of Northern Hemisphere where they form dense forests of evergreen trees. They can grow up to 80 … Read more

Spirogyra: Characteristics, Structure and Reproduction

SpirogyraCharacteristics, Structure and Reproduction

Spirogyras are common free-floating freshwater algae that inhabit ponds, pools, tanks, lakes, ditches, etc.  The word ‘Spirogyra’ is derived from the two Greek words, ‘Speria’, meaning coil, and ‘gyras’ meaning twisted. Spirogyra has many common names, including blanket weed, water silk, mermaid`s tresses, etc. It grows up to several centimeters in length and 10-100 μm … Read more

DNA : Its Structure and Functions

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DNA is also known as deoxyribonucleic acid. German biochemist Frederich Miescher first observed DNA in 1869. He termed the material nuclein, which he isolated from pus cells that he collected from bandages discarded by a nearby clinic. Frederick Griffith realized that DNA might hold genetic information in 1928. Watson, Francis Crick, Maurice Wilkins, and Rosalind Franklin figured out the double helix … Read more

Phylum Annelida: Characteristics and Classification

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The representatives of the phylum Annelida are known as segmented worms or ringed worms. Annelida is derived from Latin word ‘anellus’ meaning little ring. It is a large phylum with over 22,000 living species. Among them,  Polychaetes constitute about 12,000 species while Clitellates contains about 10,000 species. The major groups include earthworms, ragworms and leeches. … Read more