Asexual reproduction is a type of reproduction that does not involve the fusion of gametes or change in the number of chromosomes. The offspring that arise by asexual reproduction from either unicellular or multicellular organisms inherit the full set of genes of their single parent. Asexual reproduction is the primary form of reproduction for single-celled organisms such as archaea and bacteria. Many eukaryotic organisms including plants, animals, and fungi can also reproduce asexually. In vertebrates, the most common form of asexual reproduction is parthenogenesis, which is typically used as an alternative to sexual reproduction in times when reproductive opportunities are limited.
Reproduction is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. Reproduction is a fundamental feature of all known life; each individual organism exists as the result of reproduction. There are two forms of reproduction: asexual and sexual.
Pioneer species are hardy species which are the first to colonize barren environments or previously biodiverse steady-state ecosystems that have been disrupted, such as by fire. Some lichens grow on rocks without soil, so may be among the first of life forms, and break down the rocks into soil for plants. Since some uncolonized land may have thin, poor quality soils with few nutrients, pioneer species are often hardy plants with adaptations such as long roots, root nodes containing nitrogen-fixing bacteria, and leaves that employ transpiration. Note that they are often photosynthetic plants, as no other source of energy except light energy is often available in the early stages of succession, thus making it less likely for a pioneer species to be non-photosynthetic. The plants that are often pioneer species also tend to be wind-pollinated rather than insect-pollinated, as insects are unlikely to be present in the usually barren conditions in which pioneer species grow; however, pioneer species tend to reproduce asexually altogether, as the extreme or barren conditions present make it more favourable to reproduce asexually in order to increase reproductive success rather than invest energy into sexual reproduction. Pioneer species will die creating plant litter, and break down as "leaf mold" after some time, making new soil for secondary succession, and nutrients for small fish and aquatic plants in adjacent bodies of water.
Trematoda is a class within the phylum Platyhelminthes. It includes two groups of parasitic flatworms, known as flukes.
The natterjack toad is a toad native to sandy and heathland areas of Europe. Adults are 60–70 mm in length, and are distinguished from common toads by a yellow line down the middle of the back, and parallel paratoid glands. They have relatively short legs, which gives them a distinctive gait, contrasting with the hopping movement of many other toad species.
Coccidia (Coccidiasina) are a subclass of microscopic, spore-forming, single-celled obligate intracellular parasites belonging to the apicomplexan class Conoidasida. As obligate intracellular parasites, they must live and reproduce within an animal cell. Coccidian parasites infect the intestinal tracts of animals, and are the largest group of apicomplexan protozoa.
In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical manifestation of its ecological niche. Thus, habitat is a species-specific term, fundamentally different from concepts such as environment or vegetation assemblages, for which the term habitat-type is more appropriate.
Fragmentation, the splitting of cells into two parts and makes new bodies is known as fragmentation. Each fragment develops into a mature clone genetically and morphologically identical to its parent.
Incurvariidae is a family of small primitive monotrysian moths in the order Lepidoptera. There are twelve genera recognised. Many species are leaf miners and much is known of their host plants, excluding Paraclemensia acerifoliella. The most familiar species in Europe are perhaps Incurvaria masculella and Phylloporia bistrigella. The narrow wings are held tightly along the body at rest and some species have very long antennae.
Deroceras laeve, the marsh slug, is a species of small air-breathing land slug, a terrestrial pulmonate gastropod mollusk in the family Agriolimacidae.
Atrina fragilis, the fan mussel, is a species of large saltwater clam, a marine bivalve mollusc in the family Pinnidae, the pen shells.
The New Holland mouse is a species of rodent in the family Muridae. It was first described by George Waterhouse in 1843. It vanished from view for over a century before its rediscovery in Ku-ring-gai Chase National Park north of Sydney in 1967. It is found only in south east Australia, within the states of New South Wales, Queensland, Victoria, and Tasmania.
The fauna of Ireland comprises all the animal species inhabiting the island of Ireland and its surrounding waters.
The great raft spider or fen raft spider is a European species of spider in the family Pisauridae. Like other Dolomedes spiders, it is semiaquatic, hunting its prey on the surface of water. It occurs mainly in neutral to alkaline, unpolluted water of fens and grazing marsh.
Pilobolus crystallinus var. crystallinus, commonly known as the "Dung Cannon" or "Hat Thrower", is a species of fungus belonging to the Mucorales order. It is unique in that it adheres its spores to vegetation, so as to be eaten by grazing animals. It then passes through the animals' digestive systems and grows in their feces. Although these fungi only grow to be 2–4 cm (0.8–1.6 in) tall, they can shoot their sporangium, containing their spores, up to 2 m (6.6 ft) away. Due to an increase of pressure in the vesicle, the sporangium can accelerate 0–45 mph in the first millimeter of its flight, which corresponds to an acceleration of an incredible 20000 g. Using a mucus-like substance found in the vesicle of the fungus, the sporangium can adhere itself onto whatever it lands, thus completing its life cycle.
The flora of Scotland is an assemblage of native plant species including over 1,600 vascular plants, more than 1,500 lichens and nearly 1,000 bryophytes. The total number of vascular species is low by world standard but lichens and bryophytes are abundant and the latter form a population of global importance. Various populations of rare fern exist, although the impact of 19th-century collectors threatened the existence of several species. The flora is generally typical of the north west European part of the Palearctic realm and prominent features of the Scottish flora include boreal Caledonian forest, heather moorland and coastal machair. In addition to the native varieties of vascular plants there are numerous non-native introductions, now believed to make up some 43% of the species in the country.
Sexual reproduction is a type of reproduction that involves a complex life cycle in which a gamete with a single set of chromosomes (haploid) combines with another to produce an organism composed of cells with two sets of chromosomes (diploid). Sexual reproduction is the most common life cycle in multicellular eukaryotes, such as animals, fungi and plants. Sexual reproduction does not occur in prokaryotes, but they have processes with similar effects such as bacterial conjugation, transformation and transduction, which may have been precursors to sexual reproduction in early eukaryotes.
Colpoda is a genus of ciliates in the class Colpodea, order Colpodida, and family Colpodidae.
The biodiversity of Wales refers to the wide variety of ecosystems, living organisms, and the genetic makeups found in Wales.
Celypha woodiana also known as the mistletoe marble is a moth of the family Tortricidae found in Europe. In Great Britain the moth is a priority species in the United Kingdom Biodiversity Action Plan.
