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Mischogyne Gabonensis
''Mischogyne'' is a genus of plants in the family Annonaceae. It comprises five species distributed in Angola, Cameroon, Gabon, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia], Nigeria, Sierra Leone, Democratic Republic of the Congo. Arthur Wallis Exell the British botanist who first formally described the genus named it after the stalks (μίσχος, míschos, in Greek) that bears its reproductive (γυνή, gunḗ, in Greek) structures. Description Mischogyne are bushes or small trees. Their trunks are straight or branching from the base. They have elliptical to oval leaves that are arranged in an alternate phyllotaxy. The leaves are paper to leathery with a dark green upper surface and a lighter green underside. The leaves can be hairless or covered in fine downy hairs. Their inflorescences have 1-2 flowers and are extra- axillary or terminal. Their flowers have both male and female reproductive structures. Their flowers have 3 sepals that either touch one another a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arthur Wallis Exell
Arthur Wallis Exell OBE (21 May 1901, in Birmingham – 15 January 1993, in Cheltenham) was initially an assistant and later Deputy Keeper of Botany at the British Museum during the years 1924–1939 and 1950–1962. A noted cryptographer, taxonomist and phytogeographer, he was notable for his furthering of botanical exploration in tropical and sub-tropical Africa, and was an authority on the family Combretaceae. Exell's formal education started at Queen Elizabeth Grammar School in Warwickshire, and then King Edmund's School in Birmingham. From there he went on to Emmanuel College, Cambridge and was awarded an M.A. in 1926, having joined the British Museum as a second-class assistant on 11 August 1924, eventually becoming Deputy Keeper of Botany in 1950. He was entrusted with the Polypetalae, although his first paper was a morphological study of the hymenium in three species of fungus. Exell's first contact with Africa was in 1932/3 when he travelled to the islands in the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Axillary Bud
The axillary bud (or lateral bud) is an embryonic or organogenic shoot located in the axil of a leaf. Each bud has the potential to form shoots, and may be specialized in producing either vegetative shoots (stems and branches) or reproductive shoots (flowers). Once formed, a bud may remain dormant for some time, or it may form a shoot immediately. Overview An axillary bud is an embryonic or organogenic shoot which lies dormant at the junction of the stem and petiole of a plant. It arises exogenously from outer layer of cortex of the stem. Axillary buds do not become actively growing shoots on plants with strong apical dominance (the tendency to grow just the terminal bud on the main stem). Apical dominance occurs because the shoot apical meristem produces auxin which prevents axillary buds from growing. The axillary buds begin developing when they are exposed to less auxin, for example if the plant naturally has weak apical dominance, if apical dominance is broken by removi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mischogyne Gabonensis
''Mischogyne'' is a genus of plants in the family Annonaceae. It comprises five species distributed in Angola, Cameroon, Gabon, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia], Nigeria, Sierra Leone, Democratic Republic of the Congo. Arthur Wallis Exell the British botanist who first formally described the genus named it after the stalks (μίσχος, míschos, in Greek) that bears its reproductive (γυνή, gunḗ, in Greek) structures. Description Mischogyne are bushes or small trees. Their trunks are straight or branching from the base. They have elliptical to oval leaves that are arranged in an alternate phyllotaxy. The leaves are paper to leathery with a dark green upper surface and a lighter green underside. The leaves can be hairless or covered in fine downy hairs. Their inflorescences have 1-2 flowers and are extra- axillary or terminal. Their flowers have both male and female reproductive structures. Their flowers have 3 sepals that either touch one another a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mischogyne Elliotiana
''Mischogyne elliotiana'' is a species of plant in the '' Annonaceae'' family. It is native to Cameroon, Gabon, Ghana, Guinea-Bissau, Ivory Coast, Liberia, Nigeria, Sierra Leone, and Zaire. Adolf Engler and Ludwig Diels, the German botanists who first formally described the species using the basionym ''Uvaria elliotiana'', named it after George Scott-Elliot the botanist who collected the specimen they examined. Description It is a bush reaching 4-7 meters in height. Its elliptical leaves are 8-17 by 4-8 centimeters. Its hairless leaves are wedge shaped at their point of attachment and come to a long tapering point at their tips. The leaves have a papery to leathery texture and are glossy green on their upper side and lighter on their underside. The leaves have 7-13 pairs of secondary veins emanating from either side of their midribs. Its hairless petioles are 5-7 millimeters long. Its flowers are solitary or in groups of 2-4. The flowers are on 0.7-1.5 centimeter pedice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mischogyne Congensis
''Mischogyne'' is a genus of plants in the family Annonaceae. It comprises five species distributed in Angola, Cameroon, Gabon, Ghana, Guinea, Guinea-Bissau, Ivory Coast, Liberia], Nigeria, Sierra Leone, Democratic Republic of the Congo. Arthur Wallis Exell the British botanist who first formally described the genus named it after the stalks (μίσχος, míschos, in Greek) that bears its reproductive (γυνή, gunḗ, in Greek) structures. Description Mischogyne are bushes or small trees. Their trunks are straight or branching from the base. They have elliptical to oval leaves that are arranged in an alternate phyllotaxy. The leaves are paper to leathery with a dark green upper surface and a lighter green underside. The leaves can be hairless or covered in fine downy hairs. Their inflorescences have 1-2 flowers and are extra- axillary or terminal. Their flowers have both male and female reproductive structures. Their flowers have 3 sepals that either touch one another a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ovule
In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts: the ''integument'', forming its outer layer, the ''nucellus'' (or remnant of the megasporangium), and the female gametophyte (formed from a haploid megaspore) in its center. The female gametophyte — specifically termed a ''megagametophyte''— is also called the ''embryo sac'' in angiosperms. The megagametophyte produces an egg cell for the purpose of fertilization. The ovule is a small structure present in the ovary. It is attached to the placenta by a stalk called a funicle. The funicle provides nourishment to the ovule. Location within the plant In flowering plants, the ovule is located inside the portion of the flower called the gynoecium. The ovary of the gynoecium produces one or more ovules and ultimately becomes the fruit wall. Ovules are attached to the placenta in the ovary through a stalk-like structure known as a ''funiculus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stigma (botany)
The stigma () is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. Description The stigma, together with the style and ovary (typically called the stigma-style-ovary system) comprises the pistil, which is part of the gynoecium or female reproductive organ of a plant. The stigma itself forms the distal portion of the style, or stylodia, and is composed of , the cells of which are receptive to pollen. These may be restricted to the apex of the style or, especially in wind pollinated species, cover a wide surface. The stigma receives pollen and it is on the stigma that the pollen grain germinates. Often sticky, the stigma is adapted in various ways to catch and trap pollen with various hairs, flaps, or sculpturings. The pollen may be captured from the air (wind-borne pollen, anemophily), from visiting insects or other animals ( biotic pollination), or in rare cases from surrounding water (hydrophily). Stigma can vary from long and sle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Style (botany)
The stigma () is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. Description The stigma, together with the style and ovary (typically called the stigma-style-ovary system) comprises the pistil, which is part of the gynoecium or female reproductive organ of a plant. The stigma itself forms the distal portion of the style, or stylodia, and is composed of , the cells of which are receptive to pollen. These may be restricted to the apex of the style or, especially in wind pollinated species, cover a wide surface. The stigma receives pollen and it is on the stigma that the pollen grain germinates. Often sticky, the stigma is adapted in various ways to catch and trap pollen with various hairs, flaps, or sculpturings. The pollen may be captured from the air (wind-borne pollen, anemophily), from visiting insects or other animals ( biotic pollination), or in rare cases from surrounding water (hydrophily). Stigma can vary from long and slen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theca
In biology, a theca (plural thecae) is a sheath or a covering. Botany In botany, the theca is related to plant's flower anatomy. The theca of an angiosperm consists of a pair of microsporangia that are adjacent to each other and share a common area of dehiscence called the stomium. Larry Hufford, "The origin and early evolution of angiosperm stamens" i''The Anther: form, function, and phylogeny'' William G. D'Arcy and Richard C. Keating (editors), Cambridge University Press, 1996, 351pp, p.60, (from Google Books) Any part of a microsporophyll that bears microsporangia is called an anther. Most anthers are formed on the apex of a filament. An anther and its filament together form a typical (or filantherous) stamen, part of the male floral organ. The typical anther is bilocular, i.e. it consists of two thecae. Each theca contains two microsporangia, also known as pollen sacs. The microsporangia produce the microspores, which for seed plants are known as pollen grains. If t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dehiscence (botany)
Dehiscence is the splitting of a mature plant structure along a built-in line of weakness to release its contents. This is common among fruits, anthers and sporangia. Sometimes this involves the complete detachment of a part; structures that open in this way are said to be dehiscent. Structures that do not open in this way are called indehiscent, and rely on other mechanisms such as decay or predation to release the contents. A similar process to dehiscence occurs in some flower buds (e.g., ''Platycodon'', ''Fuchsia''), but this is rarely referred to as dehiscence unless wikt:circumscissile, circumscissile dehiscence is involved; anthesis is the usual term for the opening of flowers. Dehiscence may or may not involve the loss of a structure through the process of abscission. The lost structures are said to be wikt:caducous, caducous. Association with crop breeding Manipulation of dehiscence can improve crop yield since a Trait (biological), trait that causes seed dispersal i ... [...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] |
Stamen
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 ''sporangium, 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 (plant), Canna'' species or as many as 3,482 stamens which have been counted in the saguaro (''Carnegiea gigantea'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
