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Molecular Genetics
Molecular genetics is a branch of biology that addresses how differences in the structures or expression of DNA molecules manifests as variation among organisms. Molecular genetics often applies an "investigative approach" to determine the structure and/or function of genes in an organism's genome using genetic screens. The field of study is based on the merging of several sub-fields in biology: classical Mendelian inheritance, cellular biology, molecular biology, biochemistry, and biotechnology. It integrates these disciplines to explore things like genetic inheritance, gene regulation and expression, and the molecular mechanism behind various life processes. A key goal of molecular genetics is to identify and study genetic mutations. Researchers search for mutations in a gene or induce mutations in a gene to link a gene sequence to a specific phenotype. Therefore molecular genetics is a powerful methodology for linking mutations to genetic conditions that may aid th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biology
Biology is the scientific study of life and living organisms. It is a broad natural science that encompasses a wide range of fields and unifying principles that explain the structure, function, growth, History of life, origin, evolution, and distribution of life. Central to biology are five fundamental themes: the cell (biology), cell as the basic unit of life, genes and heredity as the basis of inheritance, evolution as the driver of biological diversity, energy transformation for sustaining life processes, and the maintenance of internal stability (homeostasis). Biology examines life across multiple biological organisation, levels of organization, from molecules and cells to organisms, populations, and ecosystems. Subdisciplines include molecular biology, physiology, ecology, evolutionary biology, developmental biology, and systematics, among others. Each of these fields applies a range of methods to investigate biological phenomena, including scientific method, observation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erwin Chargaff
Erwin Chargaff (11 August 1905 – 20 June 2002) was an Austro-Hungarian-born American biochemist, writer, and professor of biochemistry at Columbia University medical school. A Bucovinian Jew who immigrated to the United States during the Nazi Germany, Nazi regime, he penned a well-reviewed autobiography, ''Heraclitean Fire: Sketches from a Life Before Nature''. Through careful experimentation, Chargaff discovered two rules, called Chargaff's rules, which helped lead to the discovery of the double helix structure of DNA. Early life Chargaff was born on 11 August 1905 to a Jewish family in Czernowitz, Duchy of Bukovina, Austria-Hungary, which is now Chernivtsi, Ukraine. At the outbreak of World War I, his family moved to Vienna, where he attended the Maximiliansgymnasium (now the Gymnasium Wasagasse). He then went on to the TU Wien, Vienna College of Technology (''Technische Hochschule Wien'') where he met his future wife Vera Broido. From 1924 to 1928, Chargaff studied chemist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasmid
A plasmid is a small, extrachromosomal DNA molecule within a cell that is physically separated from chromosomal DNA and can replicate independently. They are most commonly found as small circular, double-stranded DNA molecules in bacteria and archaea; however plasmids are sometimes present in and eukaryotic organisms as well. Plasmids often carry useful genes, such as those involved in antibiotic resistance, virulence, secondary metabolism and bioremediation. While chromosomes are large and contain all the essential genetic information for living under normal conditions, plasmids are usually very small and contain additional genes for special circumstances. Artificial plasmids are widely used as vectors in molecular cloning, serving to drive the replication of recombinant DNA sequences within host organisms. In the laboratory, plasmids may be introduced into a cell via transformation. Synthetic plasmids are available for procurement over the internet by various vendors ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recombinant DNA
Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination (such as molecular cloning) that bring together genetic material from multiple sources, creating sequences that would not otherwise be found in the genome. Recombinant DNA is the general name for a piece of DNA that has been created by combining two or more fragments from different sources. Recombinant DNA is possible because DNA molecules from all organisms share the same chemical structure, differing only in the nucleotide sequence. Recombinant DNA molecules are sometimes called chimeric DNA because they can be made of material from two different species like the mythical chimera. rDNA technology uses palindromic sequences and leads to the production of sticky and blunt ends. The DNA sequences used in the construction of recombinant DNA molecules can originate from any species. For example, plant DNA can be joined to bacterial DNA, or human DNA can be joined with fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hybridization Probe
In molecular biology, a hybridization probe (HP) is a fragment of DNA or RNA, usually 15–10000 nucleotides long, which can be radioactively or fluorescently labeled. HPs can be used to detect the presence of nucleotide sequences in analyzed RNA or DNA that are complementary to the sequence in the probe. The labeled probe is first denatured (by heating or under alkaline conditions such as exposure to sodium hydroxide) into single stranded DNA (ssDNA) and then hybridized to the target ssDNA ( Southern blotting) or RNA ( northern blotting) immobilized on a membrane or '' in situ''. To detect hybridization of the probe to its target sequence, the probe is tagged (or "labeled") with a molecular marker of either radioactive or (more recently) fluorescent molecules. Commonly used markers are 32P (a radioactive isotope of phosphorus incorporated into the phosphodiester bond in the probe DNA), digoxigenin, a non-radioactive, antibody-based marker, biotin or fluorescein. DNA ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Southern Blot
Southern blot is a method used for detection and quantification of a specific DNA sequence in DNA samples. This method is used in molecular biology. Briefly, purified DNA from a biological sample (such as blood or tissue) is digested with restriction enzymes, and the resulting DNA fragments are separated by electrophoresis using an electric current to move them through a sieve-like gel or matrix, which allows smaller fragments to move faster than larger fragments. The DNA fragments are transferred out of the gel or matrix onto a solid membrane, which is then exposed to a DNA probe labeled with a radioactive, fluorescent, or chemical tag. The tag allows any DNA fragments containing complementary sequences with the DNA probe sequence to be visualized within the Southern blot. The Southern blotting combines the transfer of electrophoresis-separated DNA fragments to a filter membrane in a process called blotting, and the subsequent fragment detection by probe hybridization. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
