Modern Biological Tools and Techniques

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<p>Modern Biological tools and techniques</p> <p>Modern Biological tools and techniquesCompound MicroscopeCommonly used in schools and is equipped with lenses to enlarge objects up to several times.Used to examined cells and section of tissues with the used of light to illuminate an object being examined. </p> <p>Modern Biological tools and techniquesMicroscopeMost popular tool in Biology. Used to examine objects too small to be seen with the naked eye.Developed by Anton van Leeuwenhoek in 1670s. The most common type is Compound Microscope. </p> <p>Modern Biological tools and techniquesAnton van LeeuwenhoekIs known to have made over 500 microscopes, of which fewer than ten have survived to the present day.</p> <p>3Modern Biological tools and techniquesStereo MicroscopeUsed to examine the external structures of a specimen, such as insects. </p> <p>5Modern Biological tools and techniquesPhase-contrast MicroscopeUsed to examine highly transparent objects, such as unstained cells. </p> <p>6Modern Biological tools and techniquesElectron MicroscopeUses streams of electrons to enlarge object up to 250 000 times.</p> <p>7Modern Biological tools and techniquesTransmission Electron MicroscopeIs used to study internal structures of cells through sectioned specimens.</p> <p>8Modern Biological tools and techniquesScanning Electron MicroscopeIs used to examine the surfaces or shapes of objects, such as viruses. </p> <p>Modern Biological tools and techniquesFluorescent MicroscopeIlluminates objects stained with fluorescent dyes. Had been used extensively in studying the location of certain organelles or substances inside the cell. </p> <p>10Modern Biological tools and techniquesConfocal Scanning MicroscopeUsed to examine the 3-dimensional structure of a cell or organelles without cutting the specimen into sections. </p> <p>Modern Biological tools and techniquesDue to technological advancements in image processing, objects examined using the different microscopes can be photographed or be viewed on TV or computer screens. This process is calledvideo microscopy. Cell and tissue cultureThe use of cultured cells or tissues has an advantage over using whole animals because of ease of manipulation and simplicity of the system without the complications of other cells or substances in a whole organism. Is achieved with the use of a medium containing all the food requirements for a cell to survive grow and multiply. Is done under very strict, sterile(germ free) conditions.Is important in the production of monoclonal antibodies called hybrid technology. </p> <p>13CentrifugationCentrifugesAre instruments used to separate cells or cell organelles using centrifugal force. Ordinary table-top centrifuges are used in cell cultures to isolate whole cells from culture media.High-speed centrifuges or ultracentrifuges are used to isolate different shapes and sizes settle at the bottom of a centrifuge tube at different sedimentation rates. These are capable of spinning up to 75 000 revolutions per minute (rpm), producing forces equivalent to around 500 000 times that of Earths gravity.</p> <p>ChromatographyIt refers to a variety of techniques used to purify biological molecules, such as proteins and nucleic acids. A substance to be purified is suspended in a liquid medium (mobile phase) and is passed on to a column of matrix, such as beads (immobile phase). The substance to be purified interacts with the matrix and the interaction is used as a basis of separation.</p> <p> 15Ion Exchange ChromatographyIonic charge of a substance is used as the basis for purification.Gel Filtration ChromatographyMakes use of the size of the molecule as the basis of purification.Affinity ChromatographyUses very special and very specific interaction between two molecules.Gas Electrophoresisis a powerful technique used to separate and visualize proteins or nucleic acids. Substances to be analyzed are driven along a gel of cross- linked molecular sieves using an electric current. Substances to be analyzed are driven along a gel of cross- linked molecular sieves using an electric current. Modern Biological tools and techniquesGas Electrophoresis17Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)-It is therefore used to analyze the molecular weight of a given protein.-is used to analyze proteins based on its molecular mass. It is therefore used to analyze the molecular weight of a given protein.</p> <p>Isoelectric focusingis a type of electrophoresis that separates proteins according to isoelectric pH. Two-dimensional gel electrophoresisAn electrophoresis that combines both SDS-PAGE and isoelectric focusing Agarose gel electrophoresisis used to analyze and determine the molecular weights of nucleic acids, such as DNA or RNA.</p> <p>Modern Biological tools and techniquesTYPES OF ELECTROPHORESISSpectrophotometryIs an instrument used to determine the concentration of proteins or nucleic acids in a solution.Used in bacterial cell cultures to estimate the amount of cells present in a given volume of cell culture medium.Measure the amount of light at a specific wavelength that is absorbed by the solution, which is proportional to the concentration of substances present in the solution or the number of cells in a medium.</p> <p>Modern Biological tools and techniques</p> <p>20Polymerase Chain Reaction (PCR)Is a method used to amplify or make copies of a given DNA fragment using an enzyme called DNA polymerase.Based on a principle that a double-stranded DNA molecule breaks into two individual strands at high temperatures and with the use of PCR primers (short DNA strands), the DNA polymerase can synthesize two double-stranded DNA using two separated individual strands as templates. When the process is repeated over and over again, there is an exponential increase in the number of double- stranded DNA that is produced: from one copy to two copies to four to eight to sixteen to thirty-two, and so on, depending on how many times the cycle is repeated.Widely used as a tool in DNA cloning, analysis of genetic diseases, forensics, legal cases such as paternity testing and many more.</p> <p>Modern Biological tools and techniques21DNA SequencingIs used to determine the sequence of nucleic acids present in a given gene or DNA fragment.This technology was independently developed by Fredrick Sanger and Walter Gilbert.Most automated DNA sequencers used today are developed by Sanger.Used to prepare the DNA sample to be sequenced, followed by gel electrophoresis. The results are tabulated and analyzed by a computer.</p> <p>Modern Biological tools and techniques22ImmunoassaysRefer to a wide variety of techniques that use antibodies to recognize a very specific substance called antigen, such as protein.Widely used in the development of diagnostic kits used in hospitals to identify a particular disease or the presence of bacterial and viral infections.The pregnancy test kit is an example of an immunoassayWestern blot analysisA type of immunoassay used to confirm the identity of a protein immobilized into a membrane.Enzyme-linked immunosorbent assay (ELISA)Detects proteins or antibodies bound on a plastic plate (ELISA plate) in a liquid system. Immunofluorescence microscopyUsed to identify the location of certain organelles or proteins inside a cell.Modern Biological tools and techniques</p> <p>Immunoassays23DNA CloningIs a technique used to produce large quantities of specific DNA fragments. The process involves the ligation or linking of a gene of interest into a cloning vector, such as bacterial plasmid, that will serve as a carrier of the gene of interest. Is used in a variety of applications including gene analysis, DNA Sequencing, production of recombinant proteins and industrial and medical purpose, and the generation of transgenic animals and plants.</p> <p>Modern Biological tools and techniques24Microarrays (Gene Chips) Is a relatively new technique used to identify genes involved in a particular disease or genes involved in the different processes inside the cell. In this technique, thousands of genes are coated onto DNA chips at precise microscopic locations using robots. Based on the principle of DNA hybridization (ability of complementary strands of DNA to stick together), DNA isolated from cells, such as those from patients, are allowed to hybridize with the genes coated on the array or DNA chip. By tagging the DNA of interest with fluorescent dyes, one can determine which gene it bounds to. This technique has the advantage of identifying several genes at the same time.</p> <p>Modern Biological tools and techniques</p> <p>26</p>