Rhubarb Leaf Green

Chlorophyll

Chlorophyll is any of several related photochemical catalysts and green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words χλωρός and φύλλον. Chlorophyll allows plants to absorb energy from light. Those pigments are involved in oxygenic photosynthesis, as opposed to bacteriochlorophylls, which are related molecules found only in bacteria and involved in anoxygenic photosynthesis.

Rhubarb

Rhubarb is the fleshy, edible stalks (petioles) of species and hybrids of Rheum in the family Polygonaceae, which are cooked and used for food. The plant is a herbaceous perennial that grows from short, thick rhizomes. Historically, different plants have been called "rhubarb" in English. The large, triangular leaves contain high levels of oxalic acid and anthrone glycosides, making them poisonous and therefore inedible. The small flowers are grouped in large compound leafy greenish-white to rose-red inflorescences.

Leaf

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", while the leaves, stem, flower, and fruit collectively form the shoot system. In most leaves, the primary photosynthetic tissue is the palisade mesophyll and is located on the upper side of the blade or lamina of the leaf, but in some species, including the mature foliage of Eucalyptus, palisade mesophyll is present on both sides and the leaves are said to be isobilateral. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (adaxial) and lower (abaxial) surfaces that differ in color, hairiness, the number of stomata, the amount and structure of epicuticular wax, and other features. Leaves are mostly green in color due to the presence of a compound called chlorophyll, which is essential for photosynthesis as it absorbs light energy from the Sun. A leaf with lighter-colored or white patches or edges is called a variegated leaf.

Green

Green is the color between cyan and yellow on the visible spectrum. It has 295–350 different shades. It is evoked by light which has a dominant wavelength of roughly 495–570 nm. In subtractive color systems, used in painting and color printing, it is created by a combination of yellow and cyan; in the RGB color model, used on television and computer screens, it is one of the additive primary colors, along with red and blue, which are mixed in different combinations to create all other colors. By far the largest contributor to green in nature is chlorophyll, the chemical by which plants photosynthesize and convert sunlight into chemical energy. Many creatures have adapted to their green environments by taking on a green hue themselves as camouflage. Several minerals have a green color, including the emerald, which is colored green by its chromium content.

rhubarb

Noun

1. Any plant of the genus Rheum, especially Rheum rhabarbarum, having large leaves and long green or reddish acidic leafstalks that are edible, in particular when cooked (although the leaves are mildly poisonous).
2. The leafstalks of common rhubarb or garden rhubarb (usually known as Rheum × hybridum), which are long, fleshy, often pale red, and with a tart taste, used as a food ingredient; they are frequently stewed with sugar and made into jam or used in crumbles, pies, etc.

Adjective

1. Of the colour of rhubarb: either brownish-yellow (the colour of rhubarb rhizomes and roots used for medicinal purposes), or pale red (often the colour of the leafstalks of common rhubarb).

leaf

Noun

1. The usually green and flat organ that represents the most prominent feature of most vegetative plants.
2. A foliage leaf or any of the many and often considerably different structures it can specialise into.

Verb

1. To produce leaves; put forth foliage.
2. To divide (a vegetable) into separate leaves.

green

Noun

1. The color of grass and leaves; a primary additive color midway between yellow and blue which is evoked by light between roughly 495–570 nm.
2. A member of a green party; an environmentalist.

Adjective

1. Of a green hue.
2. Sickly, unwell.