|
Zamia Loddigesii
''Zamia loddigesii'', also known as teocinte, is a species of plant in the family Zamiaceae. It is found in Hidalgo, Oaxaca, Tamaulipas, and Veracruz states in Mexico. It is threatened by habitat loss. Description The stem is subterranean, with older ones branching. The stem is long and in diameter. There are two or three compound leaves on a stem apex, standing upright or spreading out. Leaves are long and wide. They emerge a light-green, turning to green or dark green as they mature. The petiole (leaf stalk) is long, with prickles up 4 long. The rachis (leaf midrib) is up to long, with a few prickles on the lower third of its length. There are 12 to 23 pairs of leaflets on a leaf. Median leaflets are long and wide. Like all cycads, ''Zamia loddigesii'' is dioecious, with individual plants being either male or female. There are one or two male strobili (male cones) on a stem apex, up to six cones on a plant with multiple apices. Cones are erect, cylindrical, and long ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friedrich Anton Wilhelm Miquel
Friedrich Anton Wilhelm Miquel (24 October 1811 – 23 January 1871) was a Dutch botanist, whose main focus of study was on the flora of the Dutch East Indies. Early life Miquel was born in Neuenhaus and studied medicine at the University of Groningen, where, in 1833, he received his doctorate. After starting work as a doctor at the Buitengasthuis Hospital in Amsterdam, in 1835, he taught medicine at the clinical school in Rotterdam. In 1838 he became correspondent of the Royal Institute, which later became the Royal Netherlands Academy of Arts and Sciences, and in 1846 he became member. He was professor of botany at the University of Amsterdam (1846–1859) and Utrecht University (1859–1871). He directed the Rijksherbarium (National Herbarium) at Leiden from 1862. In 1866, he was elected a foreign member of the Royal Swedish Academy of Sciences. Research Miquel did research on the taxonomy of plants. He was interested in the flora of the Dutch Empire, specifically the Dutch E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strobilus
A strobilus (plural: strobili) is a structure present on many land plant species consisting of sporangia-bearing structures densely aggregated along a stem. Strobili are often called cones, but some botanists restrict the use of the term cone to the woody seed strobili of conifers. Strobili are characterized by a central axis (anatomically a stem) surrounded by spirally arranged or decussate structures that may be modified leaves or modified stems. Leaves that bear sporangia are called '' sporophylls'', while sporangia-bearing stems are called ''sporangiophores''. Lycophytes Some members of both of the two modern classes of Lycopodiophyta ( Lycopodiopsida and Isoetopsida) produce strobili. In all cases, the lateral organs of the strobilus are microphylls, bearing sporangia. In other lycophytes, ordinary foliage leaves can act as sporophylls, and there are no organized strobili. Diphasiastrum complanatum strobilus (01).jpeg, Strobili of '' Diphasiastrum'' Lycopodium saurur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near Threatened Plants
NEAR or Near may refer to: People * Thomas J. Near, US evolutionary ichthyologist * Near, a developer who created the higan emulator Science, mathematics, technology, biology, and medicine * National Emergency Alarm Repeater (NEAR), a former alarm device to warn civilians of a foreign nuclear attack on the United States * National Emergency Airway Registry (NEAR), a patient registry for intubations in the United States * Nicking enzyme amplification reaction (NEAR), a method of DNA amplification * NEAR Shoemaker, a spacecraft that studied the near-Earth asteroid Eros * Nearness or proximity space *"Near", a city browser by NearGlobal Television, film, music, and books * Near (Death Note) The manga series ''Death Note'' features an extensive cast of fictional characters designed by Takeshi Obata with their storylines created by Tsugumi Ohba."How to Think." ''Death Note: How to Read 13''. VIZ Media. 59. The story follows the n ..., ''Nate River'', a character ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamia
''Zamia'' is a genus of cycad of the family Zamiaceae, native to North America from the United States (in Georgia and Florida) throughout the West Indies, Central America, and South America as far south as Bolivia. The genus is considered to be the most ecologically and morphologically diverse cycads, and is estimated to have originated about 68.3 million years ago. Description The genus comprises deciduous shrubs with aerial or subterranean circular stems, often superficially resembling palms. They produce spirally arranged, pinnate leaves which are pubescent, at least when young, having branched and simple, transparent and coloured hairs. The articulated leaflets lack a midrib, and are broad with subparallel dichotomous venation. Lower leaflets are not reduced to spines, though the petioles often have prickles. The emerging leaves of many ''Zamia'' species are striking, some emerging with a reddish or bronze cast ('' Z. roeslii'' being an example). ''Zamia picta'' is even more ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Flow
In population genetics, gene flow (also known as gene migration or geneflow and allele flow) is the transfer of genetic material from one population to another. If the rate of gene flow is high enough, then two populations will have equivalent allele frequencies and therefore can be considered a single effective population. It has been shown that it takes only "one migrant per generation" to prevent populations from diverging due to drift. Populations can diverge due to selection even when they are exchanging alleles, if the selection pressure is strong enough. Gene flow is an important mechanism for transferring genetic diversity among populations. Migrants change the distribution of genetic diversity among populations, by modifying allele frequencies (the proportion of members carrying a particular variant of a gene). High rates of gene flow can reduce the genetic differentiation between the two groups, increasing homogeneity. For this reason, gene flow has been thought ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetic Diversity
Genetic diversity is the total number of Genetics, genetic characteristics in the genetic makeup of a species, it ranges widely from the number of species to differences within species and can be attributed to the span of survival for a species. It is distinguished from ''genetic variability'', which describes the tendency of genetic characteristics to vary. Genetic diversity serves as a way for populations to adapt to changing environments. With more variation, it is more likely that some individuals in a population will possess variations of alleles that are suited for the environment. Those individuals are more likely to survive to produce offspring bearing that allele. The population will continue for more generations because of the success of these individuals. The academic field of population genetics includes several hypotheses and theories regarding genetic diversity. The neutral theory of evolution proposes that diversity is the result of the accumulation of neutral subs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zamia Lawsoniana
''Zamia lawsoniana'', commonly known as , is a species of plant in the family Zamiaceae. Etymology The epithet "lawsoniana" refers to the botanist John Lawson who collected specimens of the species. Classification history ''Zamia lawsoniana'' was first described in 1884 by Dyer based on a specimen from Oaxaca, Mexico. It was later reclassified as a synonym of '' Z. loddigesii''. It was removed from synonymy and restored as a valid species in 2024, and is recognized by the World Flora Online, the World List of Cycads, and Tropicos. Description ''Zamia lawsoniana'' has an underground stem, branching in older plants, up to long and in diameter. There are two to five (rarely up to 14) compound leaves on a stem apex, standing upright. Leaves are long, emerging light-green, darkening to green when mature. The petiole (leaf stalk) is long, covered with thin prickles up to long. The rachis (leaf shaft), long, is also covered with prickles on the third of it length towards the b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tabasco
Tabasco (), officially the Free and Sovereign State of Tabasco ( es, Estado Libre y Soberano de Tabasco), is one of the 32 Federal Entities of Mexico. It is divided into 17 municipalities and its capital city is Villahermosa. It is located in the southeast of the country, bordering the states of Campeche to the northeast, Veracruz to the west, and Chiapas to the south and the Petén department of Guatemala to the southeast. It has a coastline to the north with the Gulf of Mexico. Most of the state is covered in rainforest as, unlike most other areas of Mexico, it has plentiful rainfall year-round. The state is also home to La Venta, the major site of the Olmec civilization, considered to be the origin of later Mesoamerican cultures. It produces significant quantities of petroleum and natural gas. Geography The state is located in the southeast of Mexico, bordering the states of Campeche, Chiapas, and Veracruz, with the Gulf of Mexico to the north and the country of Guatemal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tropical And Subtropical Dry Broadleaf Forests
The tropical and subtropical dry broadleaf forest is a habitat type defined by the World Wide Fund for Nature and is located at tropical and subtropical latitudes. Though these forests occur in climates that are warm year-round, and may receive several hundred centimeters of rain per year, they have long dry seasons that last several months and vary with geographic location. These seasonal droughts have great impact on all living things in the forest. Deciduous trees predominate in most of these forests, and during the drought a leafless period occurs, which varies with species type. Because trees lose moisture through their leaves, the shedding of leaves allows trees such as teak and mountain ebony to conserve water during dry periods. The newly bare trees open up the canopy layer, enabling sunlight to reach ground level and facilitate the growth of thick underbrush. Trees on moister sites and those with access to ground water tend to be evergreen. Infertile sites also te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sarcotesta
The sarcotesta is a fleshy seedcoat, a type of testa. Examples of seeds with a sarcotesta are pomegranate and some cycad seeds. The sarcotesta of pomegranate seeds consists of epidermal cells derived from the integument In biology, an integument is the tissue surrounding an organism's body or an organ within, such as skin, a husk, shell, germ or rind. Etymology The term is derived from ''integumentum'', which is Latin for "a covering". In a transferred, or ..., and there are no arils on these seeds. References External links * Fruit morphology Plant anatomy {{Botany-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peduncle (botany)
In botany, a peduncle is a stalk supporting an inflorescence or a solitary flower, or, after fecundation, an infructescence or a solitary fruit. The peduncle sometimes has bracts (a type of cataphylls) at nodes. The main axis of an inflorescence above the peduncle is the rachis. There are no flowers on the peduncle but there are flowers on the rachis. When a peduncle arises from the ground level, either from a compressed aerial stem or from a subterranean stem (rhizome, tuber, bulb, corm), with few or no bracts except the part near the rachis or receptacle, it is referred to as a scape. The acorns of the pedunculate oak ''Quercus robur'', commonly known as common oak, pedunculate oak, European oak or English oak, is a species of flowering plant in the beech and oak family, Fagaceae. It is a large tree, native to most of Europe west of the Caucasus. It is wid ... are borne on a long peduncle, hence the name of the tree. See also * Pedicel (botany) * Scape (botany) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dioecy
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproduction is biparental reproduction. Dioecy has costs, since only about half the population directly produces offspring. It is one method for excluding self-fertilization and promoting allogamy (outcrossing), and thus tends to reduce the expression of recessive deleterious mutations present in a population. Plants have several other methods of preventing self-fertilization including, for example, dichogamy, herkogamy, and self-incompatibility. Dioecy is a dimorphic sexual system, alongside gynodioecy and androdioecy. In zoology In zoology, dioecious species may be opposed to hermaphroditic species, meaning that an individual is either male or female, in which case the synonym gonochory is more often used. Most animal species are dioecious (gon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Tabasco"){kind=logo}
