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Mangrove Killifish
The mangrove rivulus or mangrove killifish, ''Kryptolebias marmoratus'' ( syn. ''Rivulus marmoratus''), is a species of killifish in the family Rivulidae. It lives in brackish and marine waters (less frequently in fresh water) along the coasts of Florida, through the Antilles, and along the eastern and northern Atlantic coasts of Mexico, Central America and South America (south to Brazil). It has a very wide tolerance of both salinity (0–68 ‰)Bester, CMangrove Rivulus.Florida Museum. Retrieved 6 May 2017. and temperature (),Hill, K Smithsonian Marine Station at Fort Pierce. Retrieved 6 May 2017. can survive for about two months on land, and mostly breeds by self-fertilization. It is typically found in areas with red mangrove and sometimes lives in burrows of ''Cardisoma guanhumi'' crabs. The mangrove rivulus is up to long, but most individuals are . Overall the mangrove rivulus is widespread and not threatened, but in the United States it is considered a Species of Concern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Felipe Poey
Felipe Poey (May 26, 1799 – January 28, 1891) was a Cuban zoologist. Biography Poey was born in Havana, the son of French and Spanish parents. He spent several years (1804 to 1807) of his life in Pau, Pyrénées-Atlantiques, Pau then studied law in Madrid. He became a lawyer in Spain but was forced to leave due to his freethought, liberal ideas, returning to Cuba in 1823. He began to concentrate on the study of the natural science and traveled to France in 1825 with his wife. He began writing on the butterflies of Cuba and acquiring knowledge on fish, later supplying Georges Cuvier and Achille Valenciennes, Valenciennes with fish specimens from Cuba. He took part in the foundation, in 1832, of the Société Entomologique de France. Poey returned to Cuba in 1833 where he founded the Museum of Natural History in 1839. In 1842, he became the first professor of zoology and comparative anatomy at the University of Havana. He also took part in the creation of the Academy of Science ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Society For Experimental Biology
The Society for Experimental Biology is a learned society for animal, cell and plant biologists. It was founded in 1923 at Birkbeck College to "promote the art and science of experimental biology in all its branches". It aims to demonstrate the importance and impact of experimental biology research to the wider public and within the scientific community and to connect and support experimental biologists in their research and career development. The society has an international membership of approximately 1500, more than 20 scientific special interest groups and an outreach, education, and diversity (OED) group. Activities The main activities of the society are the organisation and sponsorship of scientific meetings, the publication of relevant research, and the promotion of development of experimental biologist through education, communication, and career development programmes. The society organises one large meeting each year, plus a number of smaller meetings. The main meeti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DNA Methylation
DNA methylation is a biological process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter (genetics), promoter, DNA methylation typically acts to repress gene Transcription (genetics), transcription. In mammals, DNA methylation is essential for normal development and is associated with a number of key processes including genomic imprinting, X-chromosome inactivation, repression of transposable elements, aging, and carcinogenesis. As of 2016, two nucleobases have been found on which natural, enzymatic DNA methylation takes place: adenine and cytosine. The modified bases are N6-methyladenine,D. B. Dunn, J. D. Smith: "The occurrence of 6-methylaminopurine in deoxyribonucleic acids". In: ''Biochem J.'' 68(4), Apr 1958, S. 627–636. [//www.ncbi.nlm.nih.gov/pubmed/13522672?dopt=Abstract PMID 13522672]. . 5-methylcytosineB. F. Vanyushin, S. G. Tkacheva, A. N. Belozers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genetics
Genetics is the study of genes, genetic variation, and heredity in organisms.Hartl D, Jones E (2005) It is an important branch in biology because heredity is vital to organisms' evolution. Gregor Mendel, a Moravian Augustinians, Augustinian friar working in the 19th century in Brno, was the first to study genetics scientifically. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring over time. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene. Phenotypic trait, Trait inheritance and Molecular genetics, molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded to study the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the Cell (bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenotype
In genetics, the phenotype () is the set of observable characteristics or traits of an organism. The term covers the organism's morphology (physical form and structure), its developmental processes, its biochemical and physiological properties, and its behavior. An organism's phenotype results from two basic factors: the expression of an organism's genetic code (its genotype) and the influence of environmental factors. Both factors may interact, further affecting the phenotype. When two or more clearly different phenotypes exist in the same population of a species, the species is called polymorphic. A well-documented example of polymorphism is Labrador Retriever coloring; while the coat color depends on many genes, it is clearly seen in the environment as yellow, black, and brown. Richard Dawkins in 1978 and again in his 1982 book '' The Extended Phenotype'' suggested that one can regard bird nests and other built structures such as caddisfly larva cases and beaver dams ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epigenetics
In biology, epigenetics is the study of changes in gene expression that happen without changes to the DNA sequence. The Greek prefix ''epi-'' (ἐπι- "over, outside of, around") in ''epigenetics'' implies features that are "on top of" or "in addition to" the traditional (DNA sequence based) genetic mechanism of inheritance. Epigenetics usually involves a change that is not erased by cell division, and affects the regulation of gene expression. Such effects on cellular and physiological traits may result from environmental factors, or be part of normal development. The term also refers to the mechanism of changes: functionally relevant alterations to the genome that do not involve mutation of the nucleotide sequence. Examples of mechanisms that produce such changes are DNA methylation and histone modification, each of which alters how genes are expressed without altering the underlying DNA sequence. Further, non-coding RNA sequences have been shown to play a key role in the r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parthenogenesis
Parthenogenesis (; from the Greek + ) is a natural form of asexual reproduction in which the embryo develops directly from an egg without need for fertilization. In animals, parthenogenesis means the development of an embryo from an unfertilized Gametophyte, egg cell. In plants, parthenogenesis is a component process of apomixis. In algae, parthenogenesis can mean the development of an embryo from either an individual sperm or an individual egg. Parthenogenesis occurs naturally in some plants, algae, invertebrate animal species (including nematodes, some tardigrades, water fleas, some scorpions, aphids, some mites, some bees, some Phasmatodea, and parasitic wasps), and a few vertebrates, such as some fish, amphibians, and reptiles. This type of reproduction has been induced artificially in animal species that naturally reproduce through sex, including fish, amphibians, and mice. Normal egg cells form in the process of meiosis and are haploid, with half as many chromosomes as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Germ Cell
A germ cell is any cell that gives rise to the gametes of an organism that reproduces sexually. In many animals, the germ cells originate in the primitive streak and migrate via the gut of an embryo to the developing gonads. There, they undergo meiosis, followed by cellular differentiation into mature gametes, either eggs or sperm. Unlike animals, plants do not have germ cells designated in early development. Instead, germ cells can arise from somatic cells in the adult, such as the floral meristem of flowering plants. Introduction Multicellular eukaryotes are made of two fundamental cell types: germ and somatic cells. Germ cells produce gametes and are the only cells that can undergo meiosis as well as mitosis. Somatic cells are all the other cells that form the building blocks of the body and they only divide by mitosis. The lineage of germ cells is called the germline. Germ cell specification begins during cleavage in many animals or in the epiblast during gastr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Inbreeding Depression
Inbreeding depression is the reduced biological fitness caused by loss of genetic diversity as a consequence of inbreeding, the breeding of individuals closely related genetically. This loss of genetic diversity results from small population size, often stemming from a population bottleneck. Biological fitness refers to an organism's ability to survive and perpetuate its genetic material. In general, the higher the genetic variation or gene pool within a breeding population, the less likely it is to suffer from inbreeding depression, though inbreeding and outbreeding depression can simultaneously occur. Inbreeding depression seems to be present in most populations of organisms, but varies across mating systems. Remarkably, hermaphroditic species often exhibit lower degrees of inbreeding depression than outcrossing species, as repeated generations of selfing is thought to purge deleterious alleles from populations. For example, the outcrossing nematode (roundworm) '' Caen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meiosis
Meiosis () is a special type of cell division of germ cells in sexually-reproducing organisms that produces the gametes, the sperm or egg cells. It involves two rounds of division that ultimately result in four cells, each with only one copy of each chromosome (haploid). Additionally, prior to the division, genetic material from the paternal and maternal copies of each chromosome is crossed over, creating new combinations of code on each chromosome. Later on, during fertilisation, the haploid cells produced by meiosis from a male and a female will fuse to create a zygote, a cell with two copies of each chromosome. Errors in meiosis resulting in aneuploidy (an abnormal number of chromosomes) are the leading known cause of miscarriage and the most frequent genetic cause of developmental disabilities. In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells, each with half the number of chromosomes as the original parent cell. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belize
Belize is a country on the north-eastern coast of Central America. It is bordered by Mexico to the north, the Caribbean Sea to the east, and Guatemala to the west and south. It also shares a maritime boundary with Honduras to the southeast. Part of the Caribbean region, Belize is a member of the Caribbean Community (CARICOM) and the Commonwealth Caribbean, the historical British West Indies. The Maya civilization spread into the area of Belize between 1500 BCE and 300 CE and flourished until about 1200. European contact began in 1502–04 when Christopher Columbus sailed along the Gulf of Honduras. European exploration was begun by English settlers in 1638. Spanish Empire, Spain and Kingdom of Great Britain, Britain both laid claim to the land until Britain defeated the Spanish in the Battle of St. George's Caye (1798). It became British Honduras, a British colony in 1840, and a Crown colony in 1862. Belize achieved its independence from the United Kingdom on 21 September ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cloning
Cloning is the process of producing individual organisms with identical genomes, either by natural or artificial means. In nature, some organisms produce clones through asexual reproduction; this reproduction of an organism by itself without a mate is known as parthenogenesis. In the field of biotechnology, cloning is the process of creating cloned organisms of Cell (biology), cells and of DNA fragments. The artificial cloning of organisms, sometimes known as reproductive cloning, is often accomplished via somatic-cell nuclear transfer (SCNT), a cloning method in which a viable embryo is created from a somatic cell and an egg cell. In 1996, Dolly (sheep), Dolly the sheep achieved notoriety for being the first mammal cloned from a somatic cell. Another example of artificial cloning is molecular cloning, a technique in molecular biology in which a single living cell is used to clone a large population of cells that contain identical DNA molecules. In bioethics, there are a vari ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
