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Ophioglossoid Fern
Ophioglossaceae, from Ancient Greek ὄφις (''óphis''), meaning "snake", and γλῶσσα (''glôssa''), meaning "tongue", also known as the adder's-tongue family, is a small family of ferns. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is the only family in the order Ophioglossales, which together with the Psilotales is placed in the subclass Ophioglossidae. The Ophioglossidae are one of the groups traditionally known as eusporangiate ferns. Members of the family differ from other ferns in a number of ways. Many have only a single fleshy leaf at a time. Their gametophytes are subterranean and rely on fungi for energy. Description Members of Ophioglossaceae are usually terrestrial (excepting a few epiphytic species of '' Ophioglossum'') and occur in both temperate and tropical areas. They differ from the other ferns in several respects: * Many species only send up one frond or leaf-blade per year, producing only a single leaf at a time. The leaves ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophioglossum Vulgatum
''Ophioglossum vulgatum'', commonly known as adder's-tongue, southern adder's-tongue or adder's-tongue fern, is a species of fern in the family ''Ophioglossaceae''. The chloroplast genome was reported to have a size of 138,562 base pairs. Description ''Ophioglossum vulgatum'' grows from a rhizome base to 10–20 cm tall (rarely to 30 cm). It consists of a two-part frond, separated into a 4-12 cm rounded diamond-shaped leaf sheath and narrow branchless spore-bearing spike. The spike has around 10-40 segments on each side. It reproduces by means of spores. Taxonomy Carl Linnaeus, Linnaeus species description, described adder's-tongue with the binomial nomenclature, binomial ''Ophioglossum vulgatum'' in his ''Species Plantarum'' of 1753. Distribution It is native to many regions with a wide scattered distribution: throughout temperate through tropical Africa and throughout the temperate Northern Hemisphere in Europe, northeastern North America, temperate Asia, and Euras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leaf
A leaf (: leaves) is a principal appendage of the plant stem, stem of a vascular plant, usually borne laterally above ground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, stem, flower, and fruit collectively form the Shoot (botany), shoot system. In most leaves, the primary Photosynthesis, photosynthetic Tissue (biology), 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. The leaf is an integral part of the stem system, and most leaves are flattened and have distinct upper (Glossary of botanical terms#adaxial, adaxial) and lower (Glossary of botanical terms#abaxial, abaxial) surfaces that differ in color, Trichome, hairiness, the number of stomata (pores that intake and output gases), the amount and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diploid
Ploidy () is the number of complete sets of chromosomes in a cell, and hence the number of possible alleles for autosomal and pseudoautosomal genes. Here ''sets of chromosomes'' refers to the number of maternal and paternal chromosome copies, respectively, in each homologous chromosome pair—the form in which chromosomes naturally exist. Somatic cells, tissues, and individual organisms can be described according to the number of sets of chromosomes present (the "ploidy level"): monoploid (1 set), diploid (2 sets), triploid (3 sets), tetraploid (4 sets), pentaploid (5 sets), hexaploid (6 sets), heptaploid or septaploid (7 sets), etc. The generic term polyploid is often used to describe cells with three or more sets of chromosomes. Virtually all sexually reproducing organisms are made up of somatic cells that are diploid or greater, but ploidy level may vary widely between different organisms, between different tissues within the same organism, and at different stages in a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophioglossum Reticulatum
''Ophioglossum reticulatum'', the netted adder's-tongue, is a species of fern in the family Ophioglossaceae. It has a pantropical/pansubtropical distribution; Latin America, the Caribbean, Sub-Saharan Africa, Madagascar, Yemen, the Indian Subcontinent, Southeast Asia, warmer parts of China, Malesia, Korea, Japan, and many tropical islands. It is a hexaploid Polyploidy is a condition in which the cells of an organism have more than two paired sets of ( homologous) chromosomes. Most species whose cells have nuclei (eukaryotes) are diploid, meaning they have two complete sets of chromosomes, one fro ... and has the highest known number of chromosomes of any plant, 720. Its leaves—or leaf, individuals only grow one per year—are edible, and are regularly consumed by people in Africa and Asia. References reticulatum Ferns of the Americas Ferns of Africa Ferns of Asia Ferns of Oceania Flora of Mexico Flora of Central America Flora of the Caribbean Flora of Southern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Organisms By Chromosome Count
The list of organisms by chromosome count describes ploidy or numbers of chromosomes in the cells of various plants, animals, protists, and other living organisms. This number, along with the visual appearance of the chromosome, is known as the karyotype, and can be found by looking at the chromosomes through a microscope. Attention is paid to their length, the position of the centromeres, banding pattern, any differences between the sex chromosomes, and any other physical characteristics. The preparation and study of karyotypes is part of cytogenetics. File:Human karyotype with bands and sub-bands.png, Karyotype of a human being. It shows 22 homologous autosomal chromosome pairs, both the female (XX) and male (XY) versions of the two sex chromosomes, as well as the mitochondrial genome (at bottom left). File:Chromosome2 merge.png, Fusion of ancestral chromosomes left distinctive remnants of telomeres, and a vestigial centromere. As other non-human extant hominidae have 48 c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Root
In vascular plants, the roots are the plant organ, organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often below the surface of the soil, but roots can also be aerial root, aerial or aerating, that is, growing up above the ground or especially above water. Function The major functions of roots are absorption of water, plant nutrition and anchoring of the plant body to the ground. Types of Roots (major rooting system) Plants exhibit two main root system types: ''taproot'' and ''fibrous'', with variations like adventitious, aerial, and buttress roots, each serving specific functions. Taproot System Characterized by a single, main root growing vertically downward, with smaller lateral roots branching off. Examples. Dandelions, carrots, and many dicot plants. Fibrous RootSystem Consists of a network of thin, branching roots that spread out from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annulus (botany)
An annulus in botany is for ferns an arc or a ring of specialized cells on the sporangium. These cells are arranged in a single row, and are associated with the release or dispersal of spores. In mosses it is a ring of cells around the tip of the sporangium. In flowers it is a ring of hairs within the flower tube. Ferns In leptosporangiate ferns, the annulus located on the outer rim of the sporangium and serves in spore dispersal. It consists typically of a ring or belt of dead water-filled cells with differentially thickened cell walls that stretches about two-thirds around each sporangium in leptosporangiate ferns. The thinner walls on the outside allow water to evaporate quickly under dry conditions. This Dehiscence (botany), dehiscence causes the cells to shrink and a contraction and straightening of the annulus ring, eventually rupturing the sporangial wall by ripping apart thin-walled lip cells on the opposite side of the sporangium. The annulus slowly straightens and conti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spore
In biology, a spore is a unit of sexual reproduction, sexual (in fungi) or asexual reproduction that may be adapted for biological dispersal, dispersal and for survival, often for extended periods of time, in unfavourable conditions. Spores form part of the Biological life cycle, life cycles of many plants, algae, fungus, fungi and protozoa. They were thought to have appeared as early as the mid-late Ordovician period as an adaptation of early land plants. Bacterial spores are not part of a sexual cycle, but are resistant structures used for survival under unfavourable conditions. Myxozoan spores release amoeboid infectious germs ("amoebulae") into their hosts for parasitic infection, but also reproduce within the hosts through the pairing of two nuclei within the plasmodium, which develops from the amoebula. In plants, spores are usually haploid and unicellular and are produced by meiosis in the sporangium of a diploid sporophyte. In some rare cases, a diploid spore is also p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Growth
In botany, secondary growth is the growth that results from cell division in the cambia or lateral meristems and that causes the stems and roots to thicken, while primary growth is growth that occurs as a result of cell division at the tips of stems and roots, causing them to elongate, and gives rise to primary tissue. Secondary growth occurs in most seed plants, but monocots usually lack secondary growth. If they do have secondary growth, it differs from the typical pattern of other seed plants. The formation of secondary vascular tissues from the cambium is a characteristic feature of dicotyledons and gymnosperms. In certain monocots, the vascular tissues are also increased after the primary growth is completed but the cambium of these plants is of a different nature. In the living pteridophytes this feature is extremely rare, only occurring in '' Isoetes''. Lateral meristems In many vascular plants, secondary growth is the result of the activity of the two lateral me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sporophyte
A sporophyte () is one of the two alternation of generations, alternating multicellular organism, multicellular phases in the biological life cycle, life cycles of plants and algae. It is a diploid multicellular organism which produces asexual Spore, spores. This stage Alternation of generations, alternates with a multicellular haploid gametophyte phase. Life cycle The sporophyte develops from the zygote produced when a haploid egg cell is fertilized by a haploid sperm and each sporophyte cell therefore has a double set of chromosomes, one set from each parent. All Embryophyta, land plants, and most multicellular algae, have life cycles in which a multicellular diploid sporophyte phase alternates with a multicellular haploid gametophyte phase. In the Spermatophyte, seed plants, the largest groups of which are the gymnosperms (bare seeds) and angiosperms (fruiting plants), the sporophyte phase is more prominent than the gametophyte, and is the familiar green plant with its roots, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Photosynthesis
Photosynthesis ( ) is a system of biological processes by which photosynthetic organisms, such as most plants, algae, and cyanobacteria, convert light energy, typically from sunlight, into the chemical energy necessary to fuel their metabolism. ''Photosynthesis'' usually refers to oxygenic photosynthesis, a process that produces oxygen. Photosynthetic organisms store the chemical energy so produced within intracellular organic compounds (compounds containing carbon) like sugars, glycogen, cellulose and starches. To use this stored chemical energy, an organism's cells metabolize the organic compounds through cellular respiration. Photosynthesis plays a critical role in producing and maintaining the oxygen content of the Earth's atmosphere, and it supplies most of the biological energy necessary for complex life on Earth. Some bacteria also perform anoxygenic photosynthesis, which uses bacteriochlorophyll to split hydrogen sulfide as a reductant instead of water, p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terrestrial Plant
A terrestrial plant is a plant that grows on, in or from land. Other types of plants are aquatic plant, aquatic (living in or on water), semiaquatic (living at edge or seasonally in water), epiphyte, epiphytic (living on other plants), and lithophyte, lithophytic (living in or on rocks). The distinction between aquatic and terrestrial plants is often blurred because many terrestrial plants are able to tolerate periodic submersion and many aquatic species have both wikt:submerse, submersed and wikt:emersed, emersed forms. There are relatively few obligate submersed aquatic plants (species that cannot tolerate emersion for even relatively short periods), but some examples include members of Hydrocharitaceae and Cabombaceae, ''Ceratophyllum'', and ''Aldrovanda'', and most macroalgae (e.g. ''Chara (alga), Chara'' and ''Nitella''). Most aquatic plants can, or prefer to, grow in the emersed form, and most only flower in that form. Many terrestrial plants can tolerate extended periods o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
