leaf wiki:
>This article is about the leaf, a plant organ. See Leaf (disambiguation) for other meanings. In botany, a leaf is an above-ground plant organ specialized for photosynthesis. For this purpose, a leaf is typically flat (laminar) and thin, to expose the chloroplast containing cells (chlorenchyma tissue) to light over a broad area, and to allow light to penetrate fully into the tissues. Leaves are also the sites in most plants where respiration, transpiration, and guttation take place. Leaves can store food and water, and are modified in some plants for other purposes. The comparable structures of ferns are correctly referred to as fronds.
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light wiki:
>For other uses, see Light (disambiguation). Light is electromagnetic radiation with a wavelength that is visible to the eye (visible light) or, in a technical or scientific setting, electromagnetic radiation of any wavelength. The three basic dimensions of light (i.e., all electromagnetic radiation) are:intensity (or brilliance or amplitude), which is related to the human perception of brightness of the light,frequency (or wavelength), perceived by humans as the color of the light, andpolarization (or angle of vibration), which is not perceptible by humans under ordinary circumstances. Due to wave-particle duality, light simultaneously exhibits properties of both waves and particles. The precise nature of light is one of the key questions of modern physics.
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