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Types of Vines

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Grapevines Grapevines are stems that climb on walls and fences by means of specialized supporting organs, called tendrils. Palmately veined leaves arise alternately along the stem. In most varieties, tendrils arise opposite two of every three successive leaves. Flowers, usually greenish, are borne in clusters and have staminate and pistillate flowers sometimes occurring on separate plants. Fruit is borne on 2-year-old canes, which are removed after harvesting the grapes. Grapes are attacked by a great number of insect pests and plant diseases, of which the most common are black rot and downy mildew. See Diseases of Plants. Scientific classification: Grapes belong to the family Vitaceae. The European grape is classified as Vitis vinifera, the northern fox grape as Vitis labrusca, the summer grape as Vitis aestivalis, the riverbank grape as Vitis riparia, and the muscadine grape as Vitis rotundifolia. Gymnosperms - (Latin gymn-, “naked”; Greek sperma, “seed”), common name for any seed-...

Gymnosperm

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Gymnosperm (Latin gymn-, “naked”; Greek sperma, “seed”), is a common name for any seed-bearing vascular plant without flowers. There are several types: the cycad , ginkgo , conifer , yew , and gnetophyte. Gymnosperms are woody plants, either shrubs, trees, or, rarely, vines (some gnetophytes). They differ from the other phylum of seed plants, the flowering plants (see Angiosperm ), in that the seeds are not enclosed in carpels but rather are borne upon seed scales arranged in cones. The gymnosperms are the most ancient seed plants; they appear to have arisen from fern ancestors in the Devonian Period. Cycads retain the most primitive characters of the extant seed plants. Gnetophytes are considered from morphological and molecular evidence to share a common ancestry with the flowering plants. Living gymnosperms are distributed worldwide, with a majority, particularly the conifers, in temperate and subarctic regions. Cycads and gnetophytes are mainly tropical to subtropical. There are ab...