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Holoparasite
An obligate parasite or holoparasite is a parasitic organism that cannot complete its life-cycle without exploiting a suitable host. If an obligate parasite cannot obtain a host it will fail to reproduce. This is opposed to a facultative parasite, which can act as a parasite but does not rely on its host to continue its life-cycle. Obligate parasites have evolved a variety of parasitic strategies to exploit their hosts. Holoparasites and some hemiparasites are obligate. It is advantageous for the parasite to preserve the health of their host when this is compatible with their nutritional and reproductive requirements, except when the death of the host is necessary for transmission.Combes, C. (1997) Fitness of Parasites: Pathology and Selection ''International Journal for Parasitology'' 27 (1): 1–10. Species Obligate parasitism is exhibited in a range of organisms, with examples in viruses, bacteria, fungi, plants, and animals.Balashov, Yu.S. (2011) Parasitism and Ecological Para ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Plant
A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All parasitic plants develop a specialized organ called the haustorium, which penetrates the host plant, connecting them to the host vasculature – either the xylem, phloem, or both. For example, plants like ''Striga'' or ''Rhinanthus'' connect only to the xylem, via xylem bridges (xylem-feeding). Alternately, plants like ''Cuscuta'' and some members of ''Orobanche'' connect to both the xylem and phloem of the host. This provides them with the ability to extract water and nutrients from the host. Parasitic plants are classified depending on the location where the parasitic plant latches onto the host (root or stem), the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their host plants by detecting volatile chemicals in the air or soil given ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemiparasite
A parasitic plant is a plant that derives some or all of its nutritional requirements from another living plant. They make up about 1% of angiosperms and are found in almost every biome. All parasitic plants develop a specialized organ called the haustorium, which penetrates the host plant, connecting them to the host vasculature – either the xylem, phloem, or both. For example, plants like ''Striga'' or ''Rhinanthus'' connect only to the xylem, via xylem bridges (xylem-feeding). Alternately, plants like ''Cuscuta'' and some members of ''Orobanche'' connect to both the xylem and phloem of the host. This provides them with the ability to extract water and nutrients from the host. Parasitic plants are classified depending on the location where the parasitic plant latches onto the host (root or stem), the amount of nutrients it requires, and their photosynthetic capability. Some parasitic plants can locate their host plants by detecting volatile chemicals in the air or soil given ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasite
Parasitism is a close relationship between species, where one organism, the parasite, lives on or inside another organism, the host, causing it some harm, and is adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), Disease vector, vector-transmitted parasitism, parasitoidism, and micropreda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitism
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of life. The entomologist E. O. Wilson has characterised parasites as "predators that eat prey in units of less than one". Parasites include single-celled protozoans such as the agents of malaria, sleeping sickness, and amoebic dysentery; animals such as hookworms, lice, mosquitoes, and vampire bats; fungi such as Armillaria mellea, honey fungus and the agents of ringworm; and plants such as mistletoe, dodder, and the Orobanchaceae, broomrapes. There are six major parasitic Behavioral ecology#Evolutionarily stable strategy, strategies of exploitation of animal hosts, namely parasitic castration, directly transmitted parasitism (by contact), wikt:trophic, trophicallytransmitted parasitism (by being eaten), Disease vector, vector-transmitted paras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parasitic Life Cycle
In biology, a biological life cycle (or just life cycle or lifecycle when the biological context is clear) is a series of changes in form that an organism undergoes, returning to the starting state. "The concept is closely related to those of the life history, development and ontogeny, but differs from them in stressing renewal." Transitions of form may involve growth, asexual reproduction, or sexual reproduction. In some organisms, different "generations" of the species succeed each other during the life cycle. For plants and many algae, there are two multicellular stages, and the life cycle is referred to as alternation of generations. The term life history is often used, particularly for organisms such as the red algae which have three multicellular stages (or more), rather than two.Dixon, P.S. 1973. ''Biology of the Rhodophyta.'' Oliver & Boyd. Life cycles that include sexual reproduction involve alternating haploid (''n'') and diploid (2''n'') stages, i.e., a change of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cuckoo
Cuckoos are birds in the Cuculidae family, the sole taxon in the order Cuculiformes . The cuckoo family includes the common or European cuckoo, roadrunners, koels, malkohas, couas, coucals and anis. The coucals and anis are sometimes separated as distinct families, the Centropodidae and Crotophagidae respectively. The cuckoo order Cuculiformes is one of three that make up the Otidimorphae, the other two being the turacos and the bustards. The family Cuculidae contains 150 species which are divided into 33 genera. The cuckoos are generally medium-sized slender birds. Most species live in trees, though a sizeable minority are ground-dwelling. The family has a cosmopolitan distribution; the majority of species are tropical. Some species are migratory. The cuckoos feed on insects, insect larvae and a variety of other animals, as well as fruit. Some species are brood parasites, laying their eggs in the nests of other species and giving rise to the metaphor ''cuckoo's egg'', ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trematoda
Trematoda is a Class (biology), class of flatworms known as flukes. They are obligate parasite, obligate internal Parasitism, parasites with a complex biological life cycle, life cycle requiring at least two Host_(biology), hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host, where the flukes sexually reproduce, is a vertebrate. Infection by trematodes can cause disease in all five traditional vertebrate classes: mammals, birds, amphibians, reptiles, and fish. Etymology Trematodes are commonly referred to as flukes. This term can be traced back to the Old English name for flounder, and refers to the flattened, rhomboidal shape of the organisms. Taxonomy There are 18,000 to 24,000 known species of trematodes, divided into two subclasses — the Aspidogastrea and the Digenea. Aspidogastrea is the smaller subclass, comprising 61 species. These flukes mainly infect Bivalvia, bivalves and Osteichthyes, bony fishes.https://www.bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tick
Ticks (order Ixodida) are parasitic arachnids that are part of the mite superorder Parasitiformes. Adult ticks are approximately 3 to 5 mm in length depending on age, sex, species, and "fullness". Ticks are external parasites, living by feeding on the blood of mammals, birds, and sometimes reptiles and amphibians. The timing of the origin of ticks is uncertain, though the oldest known tick fossils are from the Cretaceous period, around 100 million years old. Ticks are widely distributed around the world, especially in warm, humid climates. Ticks belong to two major families, the Ixodidae or hard ticks, and the Argasidae, or soft ticks. ''Nuttalliella,'' a genus of tick from southern Africa is the only member of the family Nuttalliellidae, and represents the most primitive living lineage of ticks. Adults have ovoid/pear-shaped bodies (idiosomas) which become engorged with blood when they feed, and eight legs. Their cephalothorax and abdomen are completely fused. In addit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvest Mite
Trombiculidae (); commonly referred to in North America as chiggers and in Britain as harvest mites, but also known as berry bugs, bush-mites, red bugs or scrub-itch mites, are a family of mites. Chiggers are often confused with jiggers – a type of flea. Several species of Trombiculidae in their larva stage bite their animal or human host and by embedding their mouthparts into the skin cause "intense irritation" or "a wheal, usually with severe itching and dermatitis". Trombiculidae live in forests and grasslands and are also found in the vegetation of low, damp areas such as woodlands, berry bushes, orchards, along lakes and streams, and even in drier places where vegetation is low, such as lawns, golf courses, and parks. They are most numerous in early summer when grass, weeds, and other vegetation are heaviest. In their larval stage, they attach to various animals, including humans, and feed on skin, often causing itching. These relatives of ticks are nearly microscopic, m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Head Louse
The head louse (''Pediculus humanus capitis'') is an obligate ectoparasite of humans. Head lice are wingless insects that spend their entire lives on the human scalp and feeding exclusively on human blood. Humans are the only known hosts of this specific parasite, while chimpanzees and bonobos host a closely related species, ''Pediculus schaeffi''. Other species of lice infest most orders of mammals and all orders of birds. Lice differ from other hematophagic ectoparasites such as fleas in spending their entire lifecycle on a host. Head lice cannot fly, and their short, stumpy legs render them incapable of jumping, or even walking efficiently on flat surfaces. The non-disease-carrying head louse differs from the related disease-carrying body louse (''Pediculus humanus humanus'') in preferring to attach eggs to scalp hair rather than to clothing. The two subspecies are morphologically almost identical, but do not normally interbreed. From genetic studies, they are thought to h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ramshorn Snail
The term ''ramshorn snail'' or ''ram's horn snail'' is used in two different ways. In the aquarium trade it is used to describe various kinds of freshwater snails whose shells are planispiral, meaning that the shell is a flat coil. Such shells resemble a coil of rope, or (as the name suggests) a ram's horn. In a more general natural history context, the term "ramshorn snails" is used more precisely to mean those aquatic pulmonate gastropod mollusks in the family Planorbidae that have planispiral coiled shells. Ramshorn snails have been bred for the aquarium trade and various color forms have been selected. The two species commonly found in aquariums are ''Planorbella duryi'' and ''Planorbarius corneus'', both in the family ''Planorbidae''. One species (Columbia ramshorn, Marisa cornuarietis) is from a totally different family, the ''Ampullariidae''. Ramshorn snails can sometimes become a nuisance in an aquarium, because some of them breed so profusely. Description Most of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ribeiroia Ondatrae
''Ribeiroia ondatrae'', or the frog-mutating flatworm is a parasite in the genus ''Ribeiroia'' which is believed to be responsible for many of the recent increases in amphibian limb malformations, particularly missing, malformed, and additional hind legs. It was first reported from livers of ''Ondatra'', hence its specific name. In recent studies, it was found that in areas infected with ''R. ondatrae'', the population of amphibian limb malformations was much higher than populations in which this trematode was not present. Each species studied showed varying results. For example, amphibians of species ''Pseudacris regilla'', ''Rana aurora'' and ''Taricha torosa'' were found to physically display a higher frequency in the number of abnormalities. The exact mechanism of deformation has not been determined but it has been theorized that deformation results from mechanical disruption of the cells involved in limb bud formation during the amphibian larval stage. Life cycle The fir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
