each small root forms it owns lateral rootsA root is a multicellular organ that anchors a vascular pant in the soil, absorbs minerals and water, and often stores carbohydrates. A taproot system consists of one main vertical root that gives rise to lateral roots or branch roots. Adventitious roots arise from stems or leaves. Seedless vascular plants and monocots have a fibrous root system characterized by thin lateral roots with no main root. In most plants, absorption of water and minerals occurs near the root hairs, where vast numbers of tiny root hairs increase the surface area. Many plants have modified roots.• Stems: A stem is an organ consisting of an alternating system of nodes, the points at which leaves are attached, and internodes, the stem segments between nodes. The axillary bud, which is in the upper angle formed by each leaf and the stem, is a structure that can form a lateral shoot or branch. Most axillary buds of a young shoot are dormant (not growing). An apical/terminal bud is located near the shoot tip and causes the elongation of a young shoot. Apical dominance helps maintain dormancy in most nonapical buds. Many plants have modified stems.• Leaves: In most vascular plants, the leaf is the main photosynthetic organ. (Green stems also perform photosynthesis.) Leaves generally consist of a flattened blade and a stalk called the petiole, which join the leaf to a node of the stem. Monocots and eudicots differ in the arrangement of veins, the vascular tissue of leaves: most monocots have parallel veins, and most eudicots have branching veins. In classifying angiosperms, taxonomists may use morphology (external form) as criterion. Some plant species have evolved leaves modified leaves that serve various functions. These basic organs are interdependent because roots support stems and leaves and send water and minerals, leaves make food, and stems support and exchange the two.
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