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Gynandromorphism
A gynandromorph is an organism that contains both male and female characteristics. The term comes from the Greek γυνή (''gynē'') 'female', ἀνήρ (''anēr'') 'male', and μορφή (''morphē'') 'form', and is used mainly in the field of entomology. Gynandromorphism is most frequently recognized in organisms that have strong sexual dimorphism such as certain butterflies, spiders, and birds, but has been recognized in numerous other types of organisms. Occurrence Gynandromorphism has been noted in Lepidoptera (butterflies and moths) since the 1700s. It has also been observed in crustaceans, such as lobsters and crabs, in spiders, ticks, flies, locusts, crickets, dragonflies, ants, termites, bees, lizards, snakes, rodents, and many species of birds. A notable example in birds is the zebra finch. These birds have lateralised brain structures in the face of a common steroid signal, providing strong evidence for a non-hormonal primary sex mechanism regulating brain differe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gynandromorphism In Crocothemis Servilia
A gynandromorph is an organism that contains both male and female characteristics. The term comes from the Greek γυνή (''gynē'') 'female', ἀνήρ (''anēr'') 'male', and μορφή (''morphē'') 'form', and is used mainly in the field of entomology. Gynandromorphism is most frequently recognized in organisms that have strong sexual dimorphism such as certain butterflies, spiders, and birds, but has been recognized in numerous other types of organisms. Occurrence Gynandromorphism has been noted in Lepidoptera (butterflies and moths) since the 1700s. It has also been observed in crustaceans, such as lobsters and crabs, in spiders, ticks, flies, locusts, crickets, dragonflies, ants, termites, bees, lizards, snakes, rodents, and many species of birds. A notable example in birds is the zebra finch. These birds have lateralised brain structures in the face of a common steroid signal, providing strong evidence for a non-hormonal primary sex mechanism regulating brain dif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drosophila Melanogaster
''Drosophila melanogaster'' is a species of fly (the taxonomic order Diptera) in the family Drosophilidae. The species is often referred to as the fruit fly or lesser fruit fly, or less commonly the "vinegar fly" or "pomace fly". Starting with Charles W. Woodworth's 1901 proposal of the use of this species as a model organism, ''D. melanogaster'' continues to be widely used for biological research in genetics, physiology, microbial pathogenesis, and life history evolution. As of 2017, five Nobel Prizes have been awarded to drosophilists for their work using the insect. ''D. melanogaster'' is typically used in research owing to its rapid life cycle, relatively simple genetics with only four pairs of chromosomes, and large number of offspring per generation. It was originally an African species, with all non-African lineages having a common origin. Its geographic range includes all continents, including islands. ''D. melanogaster'' is a common pest in homes, restaurants, and othe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sexual Dimorphism
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most animals and some plants. Differences may include secondary sex characteristics, size, weight, colour, markings, or behavioural or cognitive traits. These differences may be subtle or exaggerated and may be subjected to sexual selection and natural selection. The opposite of dimorphism is ''monomorphism'', which is when both biological sexes are phenotypically indistinguishable from each other. Overview Ornamentation and coloration Common and easily identified types of dimorphism consist of ornamentation and coloration, though not always apparent. A difference in coloration of sexes within a given species is called sexual dichromatism, which is commonly seen in many species of birds and reptiles. Sexual selection leads to the exaggerated dim ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lizard
Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia although some lizards are more closely related to these two excluded groups than they are to other lizards. Lizards range in size from chameleons and geckos a few centimeters long to the 3-meter-long Komodo dragon. Most lizards are quadrupedal, running with a strong side-to-side motion. Some lineages (known as "legless lizards"), have secondarily lost their legs, and have long snake-like bodies. Some such as the forest-dwelling ''Draco'' lizards are able to glide. They are often territorial, the males fighting off other males and signalling, often with bright colours, to attract mates and to intimidate rivals. Lizards are mainly carnivorous, often being sit-and-wait predators; many smaller species eat insects, while the Komodo eats mammals a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromosomes
A chromosome is a long DNA molecule with part or all of the genetic material of an organism. In most chromosomes the very long thin DNA fibers are coated with packaging proteins; in eukaryotic cells the most important of these proteins are the histones. These proteins, aided by chaperone proteins, bind to and condense the DNA molecule to maintain its integrity. These chromosomes display a complex three-dimensional structure, which plays a significant role in transcriptional regulation. Chromosomes are normally visible under a light microscope only during the metaphase of cell division (where all chromosomes are aligned in the center of the cell in their condensed form). Before this happens, each chromosome is duplicated (S phase), and both copies are joined by a centromere, resulting either in an X-shaped structure (pictured above), if the centromere is located equatorially, or a two-arm structure, if the centromere is located distally. The joined copies are now called sis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allelic
An allele (, ; ; modern formation from Greek ἄλλος ''állos'', "other") is a variation of the same sequence of nucleotides at the same place on a long DNA molecule, as described in leading textbooks on genetics and evolution. ::"The chromosomal or genomic location of a gene or any other genetic element is called a locus (plural: loci) and alternative DNA sequences at a locus are called alleles." The simplest alleles are single nucleotide polymorphisms (SNP). but they can also be insertions and deletions of up to several thousand base pairs. Popular definitions of 'allele' typically refer only to different alleles within genes. For example, the ABO blood grouping is controlled by the ABO gene, which has six common alleles (variants). In population genetics, nearly every living human's phenotype for the ABO gene is some combination of just these six alleles. Most alleles observed result in little or no change in the function of the gene product it codes for. However, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Working Paper
A working paper or work paper may be: *A working paper or technical paper. Often, authors will release working papers to share ideas about a topic or to elicit feedback before submitting to a peer reviewed conference or academic journal. Working papers are often the basis for related works, and may in themselves be cited by peer-review papers. They may be considered as grey literature. * Sometimes the term working paper is used synonymously as technical report. Working papers are typically hosted on websites, belonging either to the author or the author's affiliated institution. The United Nations uses the term "working paper" in approximately this sense for the draft of a resolution. *Documents required for a minor to get a job in certain states within the United States. Such papers usually require the employer, parent/guardian, school, and a physician to agree to the terms of work laid out by the employer. * Audit working papers: Documents required on an audit of a company ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitosis
In cell biology, mitosis () is a part of the cell cycle in which replicated chromosomes are separated into two new nuclei. Cell division by mitosis gives rise to genetically identical cells in which the total number of chromosomes is maintained. Therefore, mitosis is also known as equational division. In general, mitosis is preceded by S phase of interphase (during which DNA replication occurs) and is often followed by telophase and cytokinesis; which divides the cytoplasm, organelles and cell membrane of one cell into two new cells containing roughly equal shares of these cellular components. The different stages of mitosis altogether define the mitotic (M) phase of an animal cell cycle—the division of the mother cell into two daughter cells genetically identical to each other. The process of mitosis is divided into stages corresponding to the completion of one set of activities and the start of the next. These stages are preprophase (specific to plant cells), prophase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Papilio Androgeus
''Papilio androgeus'', the Androgeus swallowtail, queen page, or queen swallowtail, is a Neotropical butterfly of the family Papilionidae. It is found from Mexico to Argentina with a small population in southern Florida. Description The sexes are different and the female occurs in many districts in two forms. Tail narrow, pointed. Hindwing above with narrow bluish submarginal crescents, beneath with a regular row of reddish yellow crescents between cell and outer margin. Female ''P. androgeus'' has on the forewing two large yellow patches, sometimes also a small spot; in the female ''P. piranthus'' these spots are wanting or are merely indicated, the metallic scaling of the hindwing is not dense and extends into the cell.Jordan, K. , in Seitz, A. ( 1907) . The Macrolepidoptera of the World. 5: The Macrolepidoptera of the American faunistic region. Papilionidae 1-45 The wingspan is 134–140 mm. File:Papilioandrogeosmale.jpg, Male File:Papilioandrogeusfemale.jpg, Female F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bilateral Symmetry
Symmetry in biology refers to the symmetry observed in organisms, including plants, animals, fungi, and bacteria. External symmetry can be easily seen by just looking at an organism. For example, take the face of a human being which has a plane of symmetry down its centre, or a pine cone with a clear symmetrical spiral pattern. Internal features can also show symmetry, for example the tubes in the human body (responsible for transporting gases, nutrients, and waste products) which are cylindrical and have several planes of symmetry. Biological symmetry can be thought of as a balanced distribution of duplicate body parts or shapes within the body of an organism. Importantly, unlike in mathematics, symmetry in biology is always approximate. For example, plant leaves – while considered symmetrical – rarely match up exactly when folded in half. Symmetry is one class of patterns in nature whereby there is near-repetition of the pattern element, either by reflection or rotation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zebra Finch
The zebra finches are two species of estrildid finch in the genus ''Taeniopygia'' found in Australia and Indonesia. They are seed-eaters that travel in large flocks. The species are: Previously, both species were classified as a single species, the zebra finch (''T. guttata''). However, they were split by the IUCN Red List and BirdLife International in 2016. The International Ornithological Congress followed suit in 2022 based on studies noting differences in plumage, mtDNA divergence, and assortative mating between both species in captivity. The zebra finch was first captured in 1801 during Nicolas Baudin's expedition to Australia. The Indonesian species was described in 1817 by Louis Jean Pierre Vieillot in his ''Nouveau Dictionnaire d'Histoire Naturelle'', where he gave it the scientific name ''Fringilla guttata''. The Australian species was then described in 1837 by John Gould as ''Amadina castanotis''. Its current genus, ''Taeniopygia'', was described in 1862 by Ludwig R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gouldian Finch
The Gouldian finch (''Chloebia gouldiae''), also known as the Lady Gouldian finch, Gould's finch or the rainbow finch, is a colourful passerine bird that is native to Australia. Taxonomy The Gouldian finch was described by British ornithological artist John Gould in 1844 as ''Amadina gouldiae'', in honour of his deceased wife Elizabeth. The specimens were sent to him by Benjamin Bynoe although they had been described some years before by Jacques Bernard Hombron and Honoré Jacquinot. It is also known as the rainbow finch, Gould's finch, or the Lady Gouldian finch and sometimes just Gould. The Gouldian finch is sister to the parrotfinches in the genus '' Erythrura''. Description Both sexes are brightly coloured with black, green, yellow, and red markings. The females tend to be less brightly coloured. One major difference between the sexes is that the male's chest is purple, while the female's is a lighter mauve. Gouldian finches are about 125–140 mm long. Gouldian f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
