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Sunflower
The common sunflower (''Helianthus annuus'') is a species of large annual forb of the daisy family Asteraceae. The common sunflower is harvested for its edible oily seeds, which are often eaten as a snack food. They are also used in the production of cooking oil, as food for livestock, as bird food, and as plantings in domestic gardens for aesthetics. Wild plants are known for their multiple flower heads, whereas the domestic sunflower often possesses a single large flower head atop an unbranched stem. Description The plant has an erect rough-hairy stem, reaching typical heights of . The tallest sunflower on record achieved . Sunflower leaves are broad, coarsely toothed, rough and mostly alternate; those near the bottom are largest and commonly heart-shaped. Flower The plant flowers in summer. What is often called the " flower" of the sunflower is actually a "flower head" ( pseudanthium), wide, of numerous small individual five-petaled flowers (" florets"). The out ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunflower Seed
A sunflower seed is a seed from a sunflower (''Helianthus annuus''). There are three types of commonly used sunflower seeds: linoleic (most common), high oleic, and sunflower oil seeds. Each variety has its own unique levels of monounsaturated, saturated, and polyunsaturated fats. The information in this article refers mainly to the linoleic variety. For commercial purposes, sunflower seeds are usually classified by the pattern on their husks. If the husk is solid black, the seeds are called black oil sunflower seeds. The crops may be referred to as oilseed sunflower crops. These seeds are usually pressed to extract their oil. Striped sunflower seeds are primarily eaten as a snack food; as a result, they may be called confectionery sunflower seeds. The term "sunflower seed" is a misnomer when applied to the seed in its pericarp (hull). Botanically speaking, it is a cypsela. When dehulled, the edible remainder is called the sunflower kernel or heart. Production In 2022, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prairie Sunflower
''Helianthus petiolaris'' is a North American plant species in the family Asteraceae, commonly known as the prairie sunflower or lesser sunflower. Naturalist and botanist Thomas Nuttall was the first to describe the prairie sunflower in 1821. The word ''petiolaris'' in Latin means, “having a petiole”. The species originated in Western United States, but has since expanded east. The prairie sunflower is sometimes considered a weed. Distribution ''Helianthus petiolaris'' originated in the dry prairies of Minnesota, Oregon, Texas, the Dakotas, California, and other states in Western and Central United States. It has since expanded its distribution to throughout the Eastern United States and into central and western Canada. It is now the most widely distributed species of sunflower besides ''H. annuus''. Habitat and ecology Prairie sunflowers are commonly found growing in sandy areas. They can also be found in heavy clay soil and in dry prairies. They are unable to grow in sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heliotropism
Heliotropism, a form of tropism, is the diurnal or seasonal motion of plant parts (flowers or leaves) in response to the direction of the Sun. The habit of some plants to move in the direction of the Sun, a form of tropism, was already known by the Ancient Greeks. They named one of those plants after that property ''Heliotropium'', meaning "sun turn". The Greeks assumed it to be a passive effect, presumably the loss of fluid on the illuminated side, that did not need further study. Aristotle's logic that plants are passive and immobile organisms prevailed. In the 19th century, however, botanists discovered that growth processes in the plant were involved, and conducted increasingly in-depth experiments. A. P. de Candolle called this phenomenon in ''any'' plant ''heliotropism'' (1832). It was renamed phototropism in 1892 because it is a response to light rather than to the sun, and because the phototropism of algae in lab studies at that time strongly depended on the brightness (pos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Golden Angle
In geometry, the golden angle is the smaller of the two angles created by sectioning the circumference of a circle according to the golden ratio; that is, into two Arc (geometry), arcs such that the ratio of the length of the smaller arc to the length of the larger arc is the same as the ratio of the length of the larger arc to the full circumference of the circle. Algebraically, let ''a+b'' be the circumference of a circle, divided into a longer arc of length ''a'' and a smaller arc of length ''b'' such that : \frac = \frac The golden angle is then the angle subtended by the smaller arc of length ''b''. It measures approximately ...° or in radians ... . The name comes from the golden angle's connection to the golden ratio ''φ''; the exact value of the golden angle is : 360\left(1 - \frac\right) = 360(2 - \varphi) = \frac = 180(3 - \sqrt)\text or : 2\pi \left( 1 - \frac\right) = 2\pi(2 - \varphi) = \frac = \pi(3 - \sqrt)\text, where the equivalences follow from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Asteraceae
Asteraceae () is a large family (biology), family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the Order (biology), order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger family is unclear as the quantity of Extant taxon, extant species in each family is unknown. The Asteraceae were first described in the year 1740 and given the original name Composita, Compositae. The family is commonly known as the aster, Daisy (flower), daisy, composite, or sunflower family. Most species of Asteraceae are herbaceous plants, and may be Annual plant, annual, Biennial plant, biennial, or Perennial plant, perennial, but there are also shrubs, vines, and trees. The family has a widespread distribution, from subpolar to tropical regions, in a wide variety of habitats. Most occur in Hot desert climate, hot desert and cold or hot Semi-arid climate, semi-desert climates, and they are found on ever ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disk Flower
Asteraceae () is a large family of flowering plants that consists of over 32,000 known species in over 1,900 genera within the order Asterales. The number of species in Asteraceae is rivaled only by the Orchidaceae, and which is the larger family is unclear as the quantity of extant species in each family is unknown. The Asteraceae were first described in the year 1740 and given the original name Compositae. The family is commonly known as the aster, daisy, composite, or sunflower family. Most species of Asteraceae are herbaceous plants, and may be annual, biennial, or perennial, but there are also shrubs, vines, and trees. The family has a widespread distribution, from subpolar to tropical regions, in a wide variety of habitats. Most occur in hot desert and cold or hot semi-desert climates, and they are found on every continent but Antarctica. Their common primary characteristic is compound flower heads, technically known as capitula, consisting of sometimes hundreds o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudanthium
A pseudanthium (; : pseudanthia) is an inflorescence that resembles a flower. The word is sometimes used for other structures that are neither a true flower nor a true inflorescence. Examples of pseudanthia include flower heads, composite flowers, or capitula, which are special types of inflorescences in which anything from a small cluster to hundreds or sometimes thousands of flowers are grouped together to form a single flower-like structure. Pseudanthia take various forms. The real flowers (the florets) are generally small and often greatly reduced, but the pseudanthium itself can sometimes be quite large (as in the heads of some varieties of sunflower). Pseudanthia are characteristic of the daisy and sunflower family (biology), family (Asteraceae), whose flowers are differentiated into ray flowers and disk flowers, unique to this family. The disk flowers in the center of the pseudanthium are actinomorphic and the corolla (flower), corolla is fused into a tube. Flowers on th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flower
Flowers, also known as blooms and blossoms, are the reproductive structures of flowering plants ( angiosperms). Typically, they are structured in four circular levels, called whorls, around the end of a stalk. These whorls include: calyx, modified leaves; corolla, the petals; androecium, the male reproductive unit consisting of stamens and pollen; and gynoecium, the female part, containing style and stigma, which receives the pollen at the tip of the style, and ovary, which contains the ovules. When flowers are arranged in groups, they are known collectively as inflorescences. Floral growth originates at stem tips and is controlled by MADS-box genes. In most plant species flowers are heterosporous, and so can produce sex cells of both sexes. Pollination mediates the transport of pollen to the ovules in the ovaries, to facilitate sexual reproduction. It can occur between different plants, as in cross-pollination, or between flowers on the same plant or even the same f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fibonacci Number
In mathematics, the Fibonacci sequence is a Integer sequence, sequence in which each element is the sum of the two elements that precede it. Numbers that are part of the Fibonacci sequence are known as Fibonacci numbers, commonly denoted . Many writers begin the sequence with 0 and 1, although some authors start it from 1 and 1 and some (as did Fibonacci) from 1 and 2. Starting from 0 and 1, the sequence begins : 0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, ... The Fibonacci numbers were first described in Indian mathematics as early as 200 BC in work by Pingala on enumerating possible patterns of Sanskrit poetry formed from syllables of two lengths. They are named after the Italian mathematician Leonardo of Pisa, also known as Fibonacci, who introduced the sequence to Western European mathematics in his 1202 book . Fibonacci numbers appear unexpectedly often in mathematics, so much so that there is an entire journal dedicated to their study, the ''Fibonacci Quarterly''. Appli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fermat's Spiral
A Fermat's spiral or parabolic spiral is a plane curve with the property that the area between any two consecutive full turns around the spiral is invariant. As a result, the distance between turns grows in inverse proportion to their distance from the spiral center, contrasting with the Archimedean spiral (for which this distance is invariant) and the logarithmic spiral (for which the distance between turns is proportional to the distance from the center). Fermat spirals are named after Pierre de Fermat. Their applications include curvature continuous blending of curves, modeling phyllotaxis, plant growth and the shapes of certain spiral galaxy, spiral galaxies, and the design of variable capacitors, solar power reflector arrays, and cyclotrons. Coordinate representation Polar The representation of the Fermat spiral in polar coordinates is given by the equation r=\pm a\sqrt for . The parameter a is a scaling factor affecting the size of the spiral but not its shape. The tw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bird Food
Bird food or bird seed is food intended for consumption by wild, commercial, or pet birds. It is typically composed of seeds, nuts, dry fruits, flour, and may be enriched with vitamins and proteins. Bird food can vary depending upon dietary habits and beak shapes. Dietary habits refer to whether birds are naturally omnivores, carnivores, herbivores, insectivores or nectarivores. The shape of the beak, which correlates with dietary habits, is important in determining how a bird can crack the seed coat and obtain the meat of the seed. Black-oil sunflower seeds attract the widest variety of birds and are commonly used in backyard bird feeders. Using a variety of seeds can help attract specific types of birds to gardens and backyards. In general, mixtures predominantly containing red millet, oats, and other "fillers" are not attractive to most birds. These mixtures can lead to waste as the birds sort through the mix, and can potentially result in fungal and bacterial growth. W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
