Autumn leaf colorAutumn leaf color is a phenomenon that affects the normal green leaves of many deciduous trees and shrubs by which they take on, during a few weeks in the autumn season, various shades of yellow, orange, red, purple, and brown. The phenomenon is commonly called autumn colours or autumn foliage in British English and fall colors, fall foliage, or simply foliage in American English. In some areas of Canada and the United States, "leaf peeping" tourism is a major contribution to economic activity.
CarotenoidCarotenoids (kəˈrɒtɪnɔɪd) are yellow, orange, and red organic pigments that are produced by plants and algae, as well as several bacteria, archaea, and fungi. Carotenoids give the characteristic color to pumpkins, carrots, parsnips, corn, tomatoes, canaries, flamingos, salmon, lobster, shrimp, and daffodils. Over 1,100 identified carotenoids can be further categorized into two classes xanthophylls (which contain oxygen) and carotenes (which are purely hydrocarbons and contain no oxygen).
Biological pigmentBiological pigments, also known simply as pigments or biochromes, are substances produced by living organisms that have a color resulting from selective color absorption. Biological pigments include plant pigments and flower pigments. Many biological structures, such as skin, eyes, feathers, fur and hair contain pigments such as melanin in specialized cells called chromatophores. In some species, pigments accrue over very long periods during an individual's lifespan.
ChlorophyllChlorophyll (also chlorophyl) is any of several related green pigments found in cyanobacteria and in the chloroplasts of algae and plants. Its name is derived from the Greek words χλωρός , ("pale green") and φύλλον , ("leaf"). Chlorophyll allow plants to absorb energy from light. Chlorophylls absorb light most strongly in the blue portion of the electromagnetic spectrum as well as the red portion. Conversely, it is a poor absorber of green and near-green portions of the spectrum.
Chlorophyll aChlorophyll a is a specific form of chlorophyll used in oxygenic photosynthesis. It absorbs most energy from wavelengths of violet-blue and orange-red light, and it is a poor absorber of green and near-green portions of the spectrum. Chlorophyll does not reflect light but chlorophyll-containing tissues appear green because green light is diffusively reflected by structures like cell walls. This photosynthetic pigment is essential for photosynthesis in eukaryotes, cyanobacteria and prochlorophytes because of its role as primary electron donor in the electron transport chain.
LeafA leaf (: leaves) is a principal appendage of the stem of a vascular plant, usually borne laterally aboveground 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.
PigmentA pigment is a colored substance that is completely or nearly insoluble in water. In contrast, dyes are typically soluble, at least at some stage in their use. Generally dyes are often organic compounds whereas pigments are often inorganic compounds. Pigments of prehistoric and historic value include ochre, charcoal, and lapis lazuli. In 2006, around 7.4 million tons of inorganic, organic, and special pigments were marketed worldwide. According to an April 2018 report by Bloomberg Businessweek, the estimated value of the pigment industry globally is $30 billion.
BotanyBotany, also called plant science (or plant sciences), plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek word βοτάνη (botanē) meaning "pasture", "herbs" "grass", or "fodder"; βοτάνη is in turn derived from βόσκειν (), "to feed" or "to graze".
PlantPlants are eukaryotes, predominantly photosynthetic, that form the kingdom Plantae. Many are multicellular. Historically, the plant kingdom encompassed all living things that were not animals, and included algae and fungi. All current definitions exclude the fungi and some of the algae. By one definition, plants form the clade Viridiplantae (Latin for "green plants") which consists of the green algae and the embryophytes or land plants. The latter include hornworts, liverworts, mosses, lycophytes, ferns, conifers and other gymnosperms, and flowering plants.
AutumnAutumn, also known as fall in North American English, is one of the four temperate seasons on Earth. Outside the tropics, autumn marks the transition from summer to winter, in September (Northern Hemisphere) or March (Southern Hemisphere). Autumn is the season when the duration of daylight becomes noticeably shorter and the temperature cools considerably. Day length decreases and night length increases as the season progresses until the Winter Solstice in December (Northern Hemisphere) and June (Southern Hemisphere).
Chlorophyll bChlorophyll b is a form of chlorophyll. Chlorophyll b helps in photosynthesis by absorbing light energy. It is more soluble than chlorophyll a in polar solvents because of its carbonyl group. Its color is green, and it primarily absorbs blue light. In land plants, the light-harvesting antennae around photosystem II contain the majority of chlorophyll b. Hence, in shade-adapted chloroplasts, which have an increased ratio of photosystem II to photosystem I, there is a higher ratio of chlorophyll b to chlorophyll a.
ChemistryChemistry is the scientific study of the properties and behavior of matter. It is a physical science under natural sciences that covers the elements that make up matter to the compounds made of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances. Chemistry also addresses the nature of chemical bonds in chemical compounds. In the scope of its subject, chemistry occupies an intermediate position between physics and biology.
BiologyBiology is the scientific study of life. It is a natural science with a broad scope but has several unifying themes that tie it together as a single, coherent field. For instance, all organisms are made up of cells that process hereditary information encoded in genes, which can be transmitted to future generations. Another major theme is evolution, which explains the unity and diversity of life. Energy processing is also important to life as it allows organisms to move, grow, and reproduce.
CarotenosisCarotenosis is a benign and reversible medical condition where an excess of dietary carotenoids results in orange discoloration of the outermost skin layer. The discoloration is most easily observed in light-skinned people and may be mistaken for jaundice. Carotenoids are lipid-soluble compounds that include alpha- and beta-carotene, beta-cryptoxanthin, lycopene, lutein, and zeaxanthin. The primary serum carotenoids are beta-carotene, lycopene, and lutein. Serum levels of carotenoids vary between region, ethnicity, and sex in the healthy population.
AnthocyaninAnthocyanins (), also called anthocyans, are water-soluble vacuolar pigments that, depending on their pH, may appear red, purple, blue, or black. In 1835, the German pharmacist Ludwig Clamor Marquart gave the name Anthokyan to a chemical compound that gives flowers a blue color for the first time in his treatise "Die Farben der Blüthen". Food plants rich in anthocyanins include the blueberry, raspberry, black rice, and black soybean, among many others that are red, blue, purple, or black.
Habit (biology)Habit, equivalent to habitus in some applications in biology, refers variously to aspects of behaviour or structure, as follows: In zoology (particularly in ethology), habit usually refers to aspects of more or less predictable behaviour, instinctive or otherwise, though it also has broader application. Habitus refers to the characteristic form or morphology of a species. In botany, habit is the characteristic form in which a given species of plant grows (see plant habit).
CaroteneThe term carotene (also carotin, from the Latin carota, "carrot") is used for many related unsaturated hydrocarbon substances having the formula C40Hx, which are synthesized by plants but in general cannot be made by animals (with the exception of some aphids and spider mites which acquired the synthesizing genes from fungi). Carotenes are photosynthetic pigments important for photosynthesis. Carotenes contain no oxygen atoms. They absorb ultraviolet, violet, and blue light and scatter orange or red light, and (in low concentrations) yellow light.
DeciduousIn the fields of horticulture and botany, the term deciduous (dɪˈsɪdʒu.əs) means "falling off at maturity" and "tending to fall off", in reference to trees and shrubs that seasonally shed leaves, usually in the autumn; to the shedding of petals, after flowering; and to the shedding of ripe fruit. The antonym of deciduous in the botanical sense is evergreen. Generally, the term "deciduous" means "the dropping of a part that is no longer needed or useful" and the "falling away after its purpose is finished".
Lake pigmentA lake pigment is a pigment made by precipitating a dye with an inert binder, or mordant, usually a metallic salt. Unlike vermilion, ultramarine, and other pigments made from ground minerals, lake pigments are organic. Manufacturers and suppliers to artists and industry frequently omit the lake designation in the name. Many lake pigments are fugitive because the dyes involved are not lightfast. Red lakes were particularly important in Renaissance and Baroque paintings; they were often used as translucent glazes to portray the colors of rich fabrics and draperies.
FlavonoidFlavonoids (or bioflavonoids; from the Latin word flavus, meaning yellow, their color in nature) are a class of polyphenolic secondary metabolites found in plants, and thus commonly consumed in the diets of humans. Chemically, flavonoids have the general structure of a 15-carbon skeleton, which consists of two phenyl rings (A and B) and a heterocyclic ring (C, the ring containing the embedded oxygen). This carbon structure can be abbreviated C6-C3-C6.
