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Australian Ghost Shark
The Australian ghostshark (''Callorhinchus milii'') is a cartilaginous fish ( Chondrichthyes) belonging to the subclass Holocephali (chimaera). Sharks, rays and skates are the other members of the cartilaginous fish group and are grouped under the subclass Elasmobranchii. Alternative names include elephant shark, ''makorepe'' (in Māori), whitefish, plough-nose chimaera, or elephant fish. It is found off southern Australia, including Tasmania, and south of East Cape and Kaipara Harbour in New Zealand, at depths of . Morphology and biology The fish is silvery in colour with iridescent reflections and dark, variable markings on the sides. Males mature at and females at , and the maximum length head to tail is . It has an elongated body, smooth and torpedo shaped with two widely separated, triangular dorsal fins. They use their hoe-shaped snouts to probe the ocean bottom for invertebrates and small fishes. From spring to autumn, adults migrate inshore to estuaries and bays a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jean Baptiste Bory De Saint-Vincent
Jean-Baptiste Geneviève Marcellin Bory de Saint-Vincent was a French naturalist, officer and politician. He was born on 6 July 1778 in Agen (Lot-et-Garonne) and died on 22 December 1846 in Paris. Biologist and geographer, he was particularly interested in volcanology, systematics and botany. Life Youth Jean-Baptiste Bory de Saint Vincent was born at Agen on 6 July 1778. His parents were Géraud Bory de Saint-Vincent and Madeleine de Journu; his father's family were petty nobility who played important roles at the bar and in the judiciary, during and after the French Revolution. Instilled with sentiments hostile to the revolution from childhood,Biography of Jean-Baptiste Bory de Saint-Vincent on the website of the French National Assembly: http://www2.assemblee-nationale.fr/sycomore/fiche/(num_dept)/16507 he studied first at the college of Agen, then with his uncle Journu-Auber in Bordeaux in 1787. He may have attended courses in medicine and surgery from 1791 to 1793. During ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gummy Shark
The gummy shark (''Mustelus antarcticus''), also known as the Australian smooth hound, flake, sweet william or smooth dog-shark, is a shark in the family Triakidae. These small to medium-sized bottom-dwelling sharks are found mostly in, but are not limited to, the area around the southern seas of Australia and is commonly baited and fished for cuisine because of its taste and market prices. According to a 2021 paper by White, Arunrugstichai & Naylorn (2021), ''Mustelus walkeri'' (eastern spotted gummy shark) is the same animal as ''M. antarcticus''. One theory is that ''M. walkeri'' is a subpopulation of ''M. antarcticus''. Appearance This species is a slender shark with a darker grey top with white spots and a silvery-white underbelly. The gummy shark gets its name from its flat, plate-like teeth which it uses to crush its shelled and non-shelled prey. Male gummy sharks can reach a maximum length of , and females can reach up to . The minimum size of a grown male or female is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Evolution
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation tends to exist within any given population as a result of genetic mutation and recombination. Evolution occurs when evolutionary processes such as natural selection (including sexual selection) and genetic drift act on this variation, resulting in certain characteristics becoming more common or more rare within a population. The evolutionary pressures that determine whether a characteristic is common or rare within a population constantly change, resulting in a change in heritable characteristics arising over successive generations. It is this process of evolution that has given rise to biodiversity at every level of biological organisation, including the levels of species, individual organisms, and molecules. The theory of evolution by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Human Genome
The human genome is a complete set of nucleic acid sequences for humans, encoded as DNA within the 23 chromosome pairs in cell nuclei and in a small DNA molecule found within individual mitochondria. These are usually treated separately as the nuclear genome and the mitochondrial genome. Human genomes include both protein-coding DNA sequences and various types of DNA that does not encode proteins. The latter is a diverse category that includes DNA coding for non-translated RNA, such as that for ribosomal RNA, transfer RNA, ribozymes, small nuclear RNAs, and several types of regulatory RNAs. It also includes promoters and their associated gene-regulatory elements, DNA playing structural and replicatory roles, such as scaffolding regions, telomeres, centromeres, and origins of replication, plus large numbers of transposable elements, inserted viral DNA, non-functional pseudogenes and simple, highly-repetitive sequences. Introns make up a large percentage of non-coding DNA. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megabase
A base pair (bp) is a fundamental unit of double-stranded nucleic acids consisting of two nucleobases bound to each other by hydrogen bonds. They form the building blocks of the DNA double helix and contribute to the folded structure of both DNA and RNA. Dictated by specific hydrogen bonding patterns, "Watson–Crick" (or "Watson–Crick–Franklin") base pairs (guanine–cytosine and adenine–thymine) allow the DNA helix to maintain a regular helical structure that is subtly dependent on its nucleotide sequence. The complementary nature of this based-paired structure provides a redundant copy of the genetic information encoded within each strand of DNA. The regular structure and data redundancy provided by the DNA double helix make DNA well suited to the storage of genetic information, while base-pairing between DNA and incoming nucleotides provides the mechanism through which DNA polymerase replicates DNA and RNA polymerase transcribes DNA into RNA. Many DNA-binding proteins ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () ( chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with currently about 69,963 species described. Vertebrates comprise such groups as the following: * jawless fish, which include hagfish and lampreys * jawed vertebrates, which include: ** cartilaginous fish (sharks, rays, and ratfish) ** bony vertebrates, which include: *** ray-fins (the majority of living bony fish) *** lobe-fins, which include: **** coelacanths and lungfish **** tetrapods (limbed vertebrates) Extant vertebrates range in size from the frog species ''Paedophryne amauensis'', at as little as , to the blue whale, at up to . Vertebrates make up less than five percent of all described animal species; the rest are invertebrates, which lack vertebral columns. The vertebrates traditionally include the hagfish, which do no ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene Duplication
Gene duplication (or chromosomal duplication or gene amplification) is a major mechanism through which new genetic material is generated during molecular evolution. It can be defined as any duplication of a region of DNA that contains a gene. Gene duplications can arise as products of several types of errors in DNA replication and repair machinery as well as through fortuitous capture by selfish genetic elements. Common sources of gene duplications include ectopic recombination, retrotransposition event, aneuploidy, polyploidy, and replication slippage. Mechanisms of duplication Ectopic recombination Duplications arise from an event termed unequal crossing-over that occurs during meiosis between misaligned homologous chromosomes. The chance of it happening is a function of the degree of sharing of repetitive elements between two chromosomes. The products of this recombination are a duplication at the site of the exchange and a reciprocal deletion. Ectopic recombination is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Singapore
Singapore (), officially the Republic of Singapore, is a sovereign island country and city-state in maritime Southeast Asia. It lies about one degree of latitude () north of the equator, off the southern tip of the Malay Peninsula, bordering the Strait of Malacca to the west, the Singapore Strait to the south, the South China Sea to the east, and the Straits of Johor to the north. The country's territory is composed of one main island, 63 satellite islands and islets, and one outlying islet; the combined area of these has increased by 25% since the country's independence as a result of extensive land reclamation projects. It has the third highest population density in the world. With a multicultural population and recognising the need to respect cultural identities of the major ethnic groups within the nation, Singapore has four official languages: English, Malay, Mandarin, and Tamil. English is the lingua franca and numerous public services are available only in Eng ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agency For Science, Technology And Research
The Agency for Science, Technology and Research (A*STAR) is a statutory board under the Ministry of Trade and Industry of Singapore. The agency supports R&D that is aligned to areas of competitive advantage and national needs for Singapore. These span the four technology domains of Manufacturing, Trade and Connectivity, Human Health and Potential, Urban Solutions and Sustainability, and Smart Nation and Digital Economy set out under the nation's five-year R&D plan (RIE2025). The agency's research institutes are located mostly in Biopolis and Fusionopolis. The total strength of the A*STAR community, including scientists and researchers, technical and non-technical staff, and industry development and commercialization staff is approximately at 5,400. History A*STAR was established on 11 January 1991. It was formerly known as the National Science and Technology Board (NSTB) until January 2002. On 29 October 2003, Singapore's hub for the biomedical sciences, Biopolis, was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding genes, other functional regions of the genome such as regulatory sequences (see non-coding DNA), and often a substantial fraction of 'junk' DNA with no evident function. Almost all eukaryotes have mitochondria and a small mitochondrial genome. Algae and plants also contain chloroplasts with a chloroplast genome. The study of the genome is called genomics. The genomes of many organisms have been sequenced and various regions have been annotated. The International Human Genome Project reported the sequence of the genome for ''Homo sapiens'' in 200The Human Genome Project although the initial "finished" sequence was missing 8% of the genome consisting mostly of repetitive sequences. With advancements in technology that could handle sequenci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2019 ''Journal Citation Reports'' (with an ascribed impact factor of 42.778), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in autumn 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander Macmillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the journal; ''Nature'' redoubled its efforts in exp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish-and-chips
Fish and chips is a popular hot dish consisting of fried fish in crispy batter, served with chips. The dish originated in England, where these two components had been introduced from separate immigrant cultures; it is not known who created the culinary fusion that became the emblematic British meal. Often considered Britain's national dish, fish and chips is a common take-away food in the United Kingdom and numerous other countries, particularly in English-speaking and Commonwealth nations. Fish and chip shops first appeared in the UK in the 1860s, and by 1910, there were over 25,000 fish and chip shops across the UK. By the 1930s there were over 35,000 shops, but the trend reversed, and by 2009 there were only approximately 10,000. The British government safeguarded the supply of fish and chips during the First World War, and again in the Second World War; it was one of the few foods in the UK not subject to rationing during the wars. History The UK tradition of eatin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
