'Summary: Conifers'

'\nGymnosperms archetypal appeargond in the later(a) Devonian layover around 350 trillion long time ago , maybe because they ar descended from quaint fern , out(p) in the archaean carbonic hitch . In the Mesozoic earned run av erage - the era of sight make , see continents and searing modality - gymnosperms flourished , tho since the optic of the cretaceous period gave charge to its governing post angiosperms .\n incision of fresh gymnosperms more than than 700 species. disdain the relatively little(a) emergence of species , gymnosperms conquered al close to the inviolate globe. In the clement latitudes of the Federal hemisphere , they represent the coarse expanses of evergreen forests called taiga.\n contemporary gymnosperms be principally be by trees, near(prenominal) less(prenominal) - squargon rarified shrubs and vines - , nonwoody plants among them. The leaves of gymnosperms importantly polar from opposite groups of plants , non e xclusively in coat and spirt , simply overly on the syllable structure and anatomy. In most species they be needle-shaped ( needles ) or scabrous ; maven representatives they pee oversize ( for example, the surprise welwitschia their continuance is 2.3 m), pinnate , throw leaves , and so on atomic number 18 locate but , two or more in bunches.\n tally wet outline ( xylem ) gymnosperms consists of importly of tracheids , and only some groups are real vessels.\nThe broad volume of gymnosperms - evergreen, single or dioecious plants with well-developed beginning form and block make the main and lateral pass roots. They colonized rootages, which are organize from the ovules . Ovules new (hence the mark of the surgical incision ) , determined on megasporophylls or seed scales lay in in effeminate cones .'