Leaf
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A leaf is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage"
Leaf of Tilia tomentosa (silver linden tree)
Vein skeleton of a leaf. Veins contain lignin that make them harder to degrade for microorganisms.
Near the ground these Eucalyptus saplings have juvenile dorsiventral foliage from the previous year, but this season their newly sprouting foliage is isobilateral, like the mature foliage on the adult trees above.
Rosa canina: Petiole, two stipules, rachis, five leaflets
Photosynthesis
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Photosynthesis is a system of biological processes by which photopigment-bearing autotrophic organisms, such as most plants, algae and cyanobacteria, convert light energy—typically from sunlight—into
Leaf
…A leaf (pl.: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the shoot system. In most…
Composite image showing the global distribution of photosynthesis, including both oceanic phytoplankton and terrestrial vegetation. Dark red and blue-green indicate regions of high photosynthetic activity in the ocean and on land, respectively.
Plant cells with visible chloroplasts (from a moss, Plagiomnium affine)
Portrait of Jan Baptist van Helmont by Mary Beale, c. 1674
Melvin Calvin works in his photosynthesis laboratory.