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Flower Differentiation
Flower differentiation is a plant process by which the shoot apical meristem changes its anatomy to generate a flower or inflorescence in lieu of other structures. Anatomical changes begin at the edge of the meristem, generating first the outer whorls of the flower - the calyx and the corolla, and later the inner whorls of the flower, the androecium and gynoecium. Flower differentiation can take from only a few days (in annual plants) to 4–11 months (in fruit crops). The process is preceded by flower induction. Morphological Characteristics:dit Flower bud differentiation was seen to have five different stages in the flower ''M.sinostellata''. Undifferentiated stage: The flower bud was seen as yellow-green, had no scale hairs and was smooth outside. Its differentiation primordium cells are small and arranged closely. Early flower bud differentiation stage: The bud's basal region begins to expand and develops yellow-brown hairs on its outer surface. The bracts inside the gro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meristem
The meristem is a type of tissue found in plants. It consists of undifferentiated cells (meristematic cells) capable of cell division. Cells in the meristem can develop into all the other tissues and organs that occur in plants. These cells continue to divide until a time when they get differentiated and then lose the ability to divide. Differentiated plant cells generally cannot divide or produce cells of a different type. Meristematic cells are undifferentiated or incompletely differentiated. They are totipotent and capable of continued cell division. Division of meristematic cells provides new cells for expansion and differentiation of tissues and the initiation of new organs, providing the basic structure of the plant body. The cells are small, with no or small vacuoles and protoplasm fills the cell completely. The plastids (chloroplasts or chromoplasts), are undifferentiated, but are present in rudimentary form (proplastids). Meristematic cells are packed closely together wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechanism for the union of sperm with eggs. Flowers may facilitate outcrossing (fusion of sperm and eggs from different individuals in a population) resulting from cross-pollination or allow selfing (fusion of sperm and egg from the same flower) when self-pollination occurs. There are two types of pollination: self-pollination and cross-pollination. Self-pollination occurs when the pollen from the anther is deposited on the stigma of the same flower, or another flower on the same plant. Cross-pollination is when pollen is transferred from the anther of one flower to the stigma of another flower on a different individual of the same species. Self-pollination happens in flowers where the stamen and carpel mature at the same time, and are positi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inflorescence
An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed on the axis of a plant. The modifications can involve the length and the nature of the internodes and the phyllotaxis, as well as variations in the proportions, compressions, swellings, adnations, connations and reduction of main and secondary axes. One can also define an inflorescence as the reproductive portion of a plant that bears a cluster of flowers in a specific pattern. The stem holding the whole inflorescence is called a peduncle. The major axis (incorrectly referred to as the main stem) above the peduncle bearing the flowers or secondary branches is called the rachis. The stalk of each flower in the inflorescence is called a pedicel. A flower that is not part of an inflorescence is called a solitary flower and its stalk is al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (botany)
In botany, a whorl or verticil is an arrangement of leaves, sepals, petals, stamens, or carpels that radiate from a single point and surround or wrap around the stem or stalk. A leaf whorl consists of at least three elements; a pair of opposite leaves is not called a whorl. For leaves to grow in whorls is fairly rare except in plant species with very short internodes and some other genera (Galium, Nerium, Elodea etc.). Leaf whorls occur in some trees such as ''Brabejum stellatifolium'' and other species in the family Proteaceae (e.g., in the genus ''Banksia''). In plants such as these, crowded internodes within the leaf whorls alternate with long internodes between the whorls. The morphology of most flowers (called cyclic flowers) is based on four types of whorls: # The calyx: zero or more whorls of sepals at the base # The corolla: zero or more whorls of petals above the calyx # The androecium: zero or more whorls of stamens, each comprising a filament and an anther # The gyn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sepal
A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined by Noël Martin Joseph de Necker in 1790, and derived . Collectively the sepals are called the calyx (plural calyces), the outermost whorl of parts that form a flower. The word ''calyx'' was adopted from the Latin ,Jackson, Benjamin, Daydon; A Glossary of Botanic Terms with their Derivation and Accent; Published by Gerald Duckworth & Co. London, 4th ed 1928 not to be confused with 'cup, goblet'. ''Calyx'' is derived from Greek 'bud, calyx, husk, wrapping' ( Sanskrit 'bud'), while is derived from Greek 'cup, goblet', and the words have been used interchangeably in botanical Latin. After flowering, most plants have no more use for the calyx which withers or becomes vestigial. Some plants retain a thorny calyx, either dried or live, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corolla (flower)
Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corolla''. Petals are usually accompanied by another set of modified leaves called sepals, that collectively form the ''calyx'' and lie just beneath the corolla. The calyx and the corolla together make up the perianth, the non-reproductive portion of a flower. When the petals and sepals of a flower are difficult to distinguish, they are collectively called tepals. Examples of plants in which the term ''tepal'' is appropriate include genera such as '' Aloe'' and ''Tulipa''. Conversely, genera such as ''Rosa'' and '' Phaseolus'' have well-distinguished sepals and petals. When the undifferentiated tepals resemble petals, they are referred to as "petaloid", as in petaloid monocots, orders of monocots with brightly colored tepals. Since they include Liliales, an alternative ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Androecium
The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filament and an anther which contains ''microsporangia''. Most commonly anthers are two-lobed and are attached to the filament either at the base or in the middle area of the anther. The sterile tissue between the lobes is called the connective, an extension of the filament containing conducting strands. It can be seen as an extension on the dorsal side of the anther. A pollen grain develops from a microspore in the microsporangium and contains the male gametophyte. The stamens in a flower are collectively called the androecium. The androecium can consist of as few as one-half stamen (i.e. a single locule) as in '' Canna'' species or as many as 3,482 stamens which have been counted in the saguaro (''Carnegiea gigantea''). The androecium in var ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gynoecium
Gynoecium (; ) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ''pistils'' and is typically surrounded by the pollen-producing reproductive organs, the stamens, collectively called the androecium. The gynoecium is often referred to as the "female" portion of the flower, although rather than directly producing female gametes (i.e. egg cells), the gynoecium produces megaspores, each of which develops into a female gametophyte which then produces egg cells. The term gynoecium is also used by botanists to refer to a cluster of archegonia and any associated modified leaves or stems present on a gametophyte shoot in mosses, liverworts, and hornworts. The corresponding terms for the male parts of those plants are clusters of antheridia within the androecium. Flowers that bear a gynoecium but no stamens are called ''pi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annual Plants
An annual plant is a plant that completes its life cycle, from germination to the production of seeds, within one growing season, and then dies. The length of growing seasons and period in which they take place vary according to geographical location, and may not correspond to the four traditional seasonal divisions of the year. With respect to the traditional seasons, annual plants are generally categorized into summer annuals and winter annuals. Summer annuals germinate during spring or early summer and mature by autumn of the same year. Winter annuals germinate during the autumn and mature during the spring or summer of the following calendar year. One seed-to-seed life cycle for an annual plant can occur in as little as a month in some species, though most last several months. Oilseed rapa can go from seed-to-seed in about five weeks under a bank of fluorescent lamps. This style of growing is often used in classrooms for education. Many desert annuals are therophytes, beca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crop
A crop is a plant that can be grown and harvested extensively for profit or subsistence. When the plants of the same kind are cultivated at one place on a large scale, it is called a crop. Most crops are cultivated in agriculture or hydroponics. Crops may include macroscopic fungus (e.g. mushrooms) and marine macroalga (e.g. seaweed), some of which are grown in aquaculture. Most crops are harvested as food for humans or fodder for livestock. Some crops are gathered from the wild often in a form of intensive gathering (e.g. ginseng, yohimbe, and eucommia). Important non-food crops include horticulture, floriculture and industrial crops. Horticulture crops include plants used for other crops (e.g. fruit trees). Floriculture crops include bedding plants, houseplants, flowering garden and pot plants, cut cultivated greens, and cut flowers. Industrial crops are produced for clothing ( fiber crops e.g. cotton), biofuel ( energy crops, algae fuel), or medicine ( medicinal plants). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flower Induction
Flower induction is the physiological process in the plant by which the shoot apical meristem becomes competent to develop flowers. Biochemical changes at the apex, particularly those caused by cytokinins, accompany this process. Usually flower induction is followed by flower differentiation, with some notable exceptions such as in kiwifruit Kiwifruit (often shortened to kiwi in North American, British and continental European English) or Chinese gooseberry is the edible berry of several species of woody vine A vine (Latin ''vīnea'' "grapevine", "vineyard", from ''vīnum'' ..., where the two processes are separated. Flower induction can be reversed, but flower differentiation is irreversible, because anatomical changes are in place. References Plant physiology {{plant-physiology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bract
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or of a different color, shape, or texture. Typically, they also look different from the parts of the flower, such as the petals or sepals. A plant having bracts is referred to as bracteate or bracteolate, while one that lacks them is referred to as ebracteate and ebracteolate, without bracts. Variants Some bracts are brightly-coloured and serve the function of attracting pollinators, either together with the perianth or instead of it. Examples of this type of bract include those of ''Euphorbia pulcherrima'' (poinsettia) and ''Bougainvillea'': both of these have large colourful bracts surrounding much smaller, less colourful flowers. In grasses, each floret (flower) is enclosed in a pair of papery bracts, called the lemma (lower bract) and p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
