KPK Board 12th Class Biology Ch 26 Biotechnology Short Questions Answers

It is a branch of Biology that deals with methods and techniques to use living organisms for the Welfare of man.

The importance of biotechnology can be understood by the fact that its development has been associated with almost every field. Improving health biotechnology has a vital role in improving health by medicines. Improving the environment is also helpful in improving the environment by the introduction of methods for disposal.

It is a field of biotechnology in which genetic material from one organism is transferred to another.Aim  the aim of genetic engineering is to introduce the gene of choice to the organism for production of better varieties and for the cure of different genetic disorders.

The following are some important uses of genetic engineering.

With the help of genetic engineering we have the ability to find specific genes. The gene has been implicated countless times to harvest their protein product in large quantity.several important species can we grow from a single cell. Recombinant DNA technology is able to alter the genome of organisms.

The main objectives of genetic engineering are.

to identify  and isolate the disease causing gene.To find out remedies and therapies to treat other non genetic diseases. to make More effective medicines. production of genetically modified organisms. production of antibiotics and hormones from genetically engineered plants and animals.

The basic technique of genetic engineering is the following.

DNA or gene of interest from a donor is isolated through restriction enzymes. attachment genes are attached to vectors (plasmid)that act as a vehicle for carrying the desired gene. joining: DNA fragments of donor and vector are joined together. The process is known as splicing.

Hybrid DNA: as a result of these steps a recombinant or hybrid DNA is obtained.

It has improved nutritional quality. It helps in better nitrogen fixation that is required for soil fertility.it helps in preparation for herbicide resistant plant.insect resistant varieties are also formed.the plants are enabled to resist various diseases.genetic engineering help to enhance the efficiency of minerals.

The isolated proteins are the total cell material from a variety of microorganisms bacteria , yeast algae and fungi used as food or feed are called single cell protein. Microbes produce yeast  (saccharomyces cerevisiae) bacteria (rhodopseudomonas) algae ( chlorella) which can use a broad spectrum of raw material as a carbon source.

It is an in vivo method used when gene cloning is required at industrial scale .requirements: gene of interest. Molecular scissors. Molecular carrieres. Molecular glue. Expression system. 

Restriction endo- nucleases are enzymes that cleave the bond of both DNA strands within a stretch of just a few basis.

Number:  several thousand endo- nucleases have been isolated.

Occurrence: naturally restriction enzymes are found in bacteria.

Names: the restriction enzymes are named after their host origin.

E.COR-I

Hind I and II

Xhol

Vectors are the molecular careers that act as a vehicle for carrying foregin gene into host cell. plasmid the mostly used Vector are plasmid that are the small circular DNA molecule of bacteria Small vector relative the small vectors are more desirable because they increase the transformation efficiency and are easy to manipulate. polylinker it is a unique restriction site of vector that is specific for foreign gene it is also known as mcs the multiple cloning site.

DNA ligase is an enzyme that is used for the formation of phosphodiester linkage between two adjacent nucleotides. site of action the linkage is formed between the 3 |0 H and5|po4 Of adjacent nucleotide.experiments in DNA experiments DNA ligase is used to join two different DNA segments that are plasmid and the foreign DNA.

types there are different types of DNA ligase but most oftenly use is tu DNA ligase.

A  suitable organism  that can act as a host for the Recombinant vector to express is called the expression system. selection The selection of suitable expression systems always depends on the type of vector which is being used while making Recombinant DNA. The most important character of an ideal expression system is its short generation time and its simplicity of genetic System. For example, bacteria cells act as an ideal expression system.

isolation first of all the gene of choice is isolated. vector site then the particular site of factor on which the gene of choice may be introduced is cut open by restriction system.  Incubation The linearized vector and target DNA are incubated together in the presence of DNA ligase. At last the phosphodiester linkage is established between then for a Recombinant DNA is formed.

It is a suitable organism that can act as a host for Recombinant vectors.

transformation transformation can be performed by putting the expression system and plasmid in the same medium.  calcium chloride it is used for permeability bacterial cell take up Recombinant Plasma in presence of calcium chloride. reproduction as the cells reproduce bacterial colonies are formed and contain the gene of interest with Express itself and make a product.

The transformed clone can be identified by adding particula antibiotic for which the resistant gene is found in plasmid. Process  as the transformed has got resistance against the antibiotic for it remains alive and continues to grow. As a result untransformed clones are killed by antibiotics.Product from the transformed bacterial clones the product can be separated.

it stands for polymerase chain reaction. definition PCR is a technique used for cloning a single or a few copies of DNA to generate thousands of copies. inventor it was invented by Kary mullis in 1983 and was given the Nobel Prize in 1993. basis it is based upon in vitro replication process carried out by DNA polymerase .Process in this process the polymerase is completed to polymerase are given a piece of DNA again and again so that  multiple copies are produced which is great enough to observe visually. 

PCR is a polymer chain reaction that produces multiple copies of a given gene. Components  following are the components of PCR.

template DNA may be a useful gene or piece of DNA. dNTPs It is a  deoxyribonucleoside triphosphate, the free nuclear tide acting as a raw material for new DNA fragments.  primer two types.Forward primer and backward primer. taq polymerase is a temperature tolerant enzyme that catalyse the synthesis of DNA.

PCR reaction consists of following steps.

Denaturation:  in this   step template DNA is heated to 94C for 1-5  minutes, thus  forming ( SSDNA)  the single stranded.   Primer annealing  in this step the two primers hybridize the (SSDNA) at its complementary region; it is done at 45C for 2 minutes. extension it is the final step in which taq DNA polymerase synthesise the new strand at 72c  just for a minute.

Diagnostic:  it is an efficient Diagnostic technique, E.G. HBV,HIV, HCV,etc.

Food samples:  it is used to detect microorganisms in food samples, water etc.

genome analysis:  it can be used for the genome analysis.

DNA Sequencing:  reactions for DNA Sequencing are simplified by PCR.

crime detection:  PCR is useful for crime detection.

DNA fingerprinting:  it is an important application of PCR.

It is a collection of bacterial bacteriophage clones each containing at least one copy of every DNA sequence in the genome. a construction genomic library is formed when the genome fragment of the organism is extracted and is cut into fragments of suitable size.Methods  the important methods used for constructing a genomic library are following.

enzymatic digestion

non enzymatic digestion

partial enzymatic digestion.

It is a process of determining the precise order of nucleotides within a DNA molecule.

Principles:  the main principles in DNA Sequencing are.

fragmentation to generate DNA pieces of different sizes.

separation the different pieces of DNA are separated by gel electrophoresis.

reading the sequence is then read out from the gel.

It is a widely used and similar method to natural DNA replication.

Inventor:  the method was developed by Frederick Sanger and Andrew Coulson in 1977.

Denaturing,  tagging, division, PCR machine.

It is a technique used to separate the charge sharing (  protein, RNA and DNA) under the influence of the electric field.

Criteria:  in this technique DNA fragments are separated by size.  The gel the most commonly used is agarose and polyacrylamide .Electric field :  the gel slab is suspended in a buffer solution used to establish electric field .electric current:  as the electric current Run between the electrodes,  the DNA fragments of different length begin to move from negative to positive pole.

Appearance:  when the movement is stopped the DNA molecules appear as a band at different positions.

DNA Sequencing in automatic Sequencing machines is called automatic DNA Sequencing different from other methods. It has greatly improved quality. its speed is significant. There is no need for radiolabeling and Autoradiography.  Each of the four (ddNTPs) are labelled with a specific dye.So that specific colour can be attributed to the presence of a particular base the sequence is read by computer.

It is a DNA Sequencing method also called the chemical cleavage method invention. The method was for the first time developed by Allan Maxam and Walter Gilbert in  1977 .Process following steps are involved in this method. DNA sequence is end labelled at one end.DMSOThe diameter sulfoxide is added at 99 centigrade to breakdown base pairing. the two strands are separated from one another one stand is purified and divided into four samples each of which is treated with   cleavage reagent.

It is a technique to assess the identification of individual By their respective DNA profile. human DNA human DNA not only has a record of each person’s individuality but  also a phylogeny.

DNA analysis can be used for defining paternity . predisposition  to a disease. embryonic health criminal guilt or Innocence identify endangered and protected species match organ Donor and recipient determine Pedigree.

This different way of mapping is distinguished The genetic mapping uses classical genetic techniques Pedigree analysis for breeding experiment using modern Molecular Biology techniques for same purpose.

These are the landmark of genetic maps that describe any observable variation that result from alterations are mutations at a single locus type they can be with In genes that code for noticeable physical Character such as eye colour within a non coding region of gene. RFLPs, VNTRs, SNPs.

Human Genome Project is an  international scientific research project with data mining the Sequencing of chemical base pairs of human DNA. major goal of hgp. identify 20 and 25,000 genes in humans. determined sequence of 3 billion chemical based pairs. store the information. improved tools for data analysis transfer related Technologies address the ethical legal and social as you arising from HGP .

It is the propagation of a plant by using a single cell and a group of cells in a test tube under controller hygienic conditions.  explant the initial plant part used to develop tissue culture is called explant. procedure sterilization is the process in which plant materials are made germ free by using antiseptic chemicals. media preparation in tissue culture the explants are grown on artificial media in which composition is kept constant. insulation it is the  placement  of explants onto the solid culture medium.callus  first the text plants grow into an organised mass of cell called callus which is then shifted to new media for development of roots and shoots .

Plantlets as the callus grow pieces are typically sliced and transferred to new media to grow a normal plant.

callus culture:  when explanations are cultured on suitable media with growth hormones,  and it gives rise to unorganised mass of cell called callus,  it is the callus culture.Cell suspension culture  it is developed from callus that is placed on liquid medium.

protoplast culture is most commonly isolated from mesophyll and cell suspension.

Meristem culture The specially growing part at tips of roots and shoots are called meristem .Generally the roots and shoots  of apical meristem are used for meristem culture.

Another culture is a Pollen culture in which mature  pollens are cultured at suitable medium.

production of antiviral vaccines. Genetic manipulation which is easy to carry out in cells is organ culture production of monoclonal antibodies required in cell lines in culture production of Pharmaceutical drugs using cell lines chromosome analysis of cells  derived  from the womb.

study of the effects of toxins and pollutants using cell lines use of artificial skin study the function of the Nerve cells.

the organisms in which the Recombinant DNA technology is used are called transgenic organisms they are also called genetically engineered are genetically modified organisms that carry the foreign genes.

vaccines biotechnology has made a vital role in improving health these are important chemicals used to enhance the body immunity genetic engineering help in production of many types of vaccines. diagnosis of disease many human diseases can be diagnosed by using products of biotechnology.

monoclonal antibodies are a group of identical antibodies they are made by identical immune cells that all are clones of a unique parental cell. These antibodies are used to  therapeutically  protect against disease they can also be used to diagnose various diseases process manually the monoclonal antibodies are made by using Myeloma cells with spleen  cells from a mouse immunised with a desired gene. 

it is a technique for correcting the defective jeans responsible for this is development process or normal gene may be inserted into non specific location in genome to replace non-functional gene and abnormal gene can be swapped for a normal gene for the homologous recombination the abnormal gene could be repaired the population of a particular gene could be altered.

it is a technique for correcting a defective gene.

mechanism in gene therapy the normal genes are delivered by two methods.

in Vivo:  in this method the gene is delivered directly into the body.  Ex Vivo in this method the gene is delivered outside the body vector. In both cases practice must be used to deliver the gene to the patients with target cells currently the most common vector is a virus. target cells such as patients’ liver or lungs are infected with vector the generation of functional protein product from the therapeutic gene restores the target cell to normal condition.

It is an autosomal recessive genetic disorder that affects mostly.  the lungs also the pancreas and liver characterized by abnormal transport of chloride and sodium across epithelium teaching to a thick viscous secretion.

The (GM) differ greatly from the traditional breathing practices .Genetic engineering violates the natural boundaries and reproduction.  According to Dr Stanley Ewan , Eating food can lead to stomach and colon cancer.

There are two reasons for it.

bacteria add methyl group to its enzyme for identification so the genome of bacteria is structured into a ring so there are no free ends for enzymes to work on.

suitable cloning site

selectable markers

reporter genes

elements for expression. 

cells are grown and maintained and appropriate temperature and gas mixture in  the cell incubator.The second important condition is stable growth medium.

(HGH)s  human growth hormones are used to treat dwarfism.  Human insulin is used to treat diabetes.

These are fragments of DNA and RNA of variable length used in DNA and RNA samples to detect the presence of nucleotide sequences.

to detect the hybridization of the  probe  to its target sequence the probes  are labelled with molecular markers.

Plasmids

Bacteriophage

Cosmid

bacterial artificial chromosome

yeast artificial chromosomes

human artificial chromosomes