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A tree structure, tree diagram, or tree model is a way of representing the hierarchical nature of a structure in a graphical form. It is named a "tree structure" because the classic representation resembles a tree, although the chart is generally upside down compared to a biological tree, with the "stem" at the top and the "leaves" at the bottom.
Pinus monophylla, the single-leaf pinyon, (alternatively spelled piñon) is a pine in the pinyon pine group, native to North America. The range is in southernmost Idaho , western Utah , Arizona , southwest New Mexico , Nevada , eastern and southern California and northern Baja California .
In many species with spirally arranged leaves, such as Abies grandis (pictured), the leaf bases are twisted to present the leaves in a very flat plane for maximum light capture. Leaf size varies from 2 mm in many scale-leaved species, up to 400 mm long in the needles of some pines (e.g. Apache pine, Pinus engelmannii ).
Members of the family Pinaceae are trees (rarely shrubs) growing from 2 to 100 metres (7 to 300 feet) tall, mostly evergreen (except the deciduous Larix and Pseudolarix), resinous, monoecious, with subopposite or whorled branches, and spirally arranged, linear (needle-like) leaves. [3] The embryos of Pinaceae have three to 24 cotyledons.
It also transports water and nutrients from the roots to the aerial parts of the tree, and distributes the food produced by the leaves to all other parts, including the roots. [ 62 ] In the case of angiosperms and gymnosperms, the outermost layer of the trunk is the bark , mostly composed of dead cells of phellem (cork). [ 63 ]
Pine trees are evergreen, coniferous resinous trees (or, rarely, shrubs) growing 3–80 metres (10–260 feet) tall, with the majority of species reaching 15–45 m (50–150 ft) tall. [7] The smallest are Siberian dwarf pine and Potosi pinyon , and the tallest is an 83.45 m (273.8 ft) tall sugar pine located in Yosemite National Park .
The members of the pine family (pines, spruces, firs, cedars, larches, etc.) have cones that are imbricate (that is, with scales overlapping each other like fish scales).). These cones, especially the woody female cones, are considered the "archetypal" tree cones.The female cone has two types of scale: the bract scales, and the seed scales (or ovuliferous scales), one subtended by each bract ...
Root hairs of older portions of roots are destroyed over time, and only at a certain region near a growing apex (called the root-hair-region) are root hairs seen. Although microscopic, root-hairs can be observed by the unaided eye in chili and Brassica seedlings.