BT301 Final Term Subjective

BT301 SUBJECTIVES · FINAL TERM- 100% · Introduction-to-Biotechnology · GUESS PAPER 2024 · BY SULMAN ALI GUJJAR · SUBJECTIVES · Difference between pBR322 and pBR325:

pBR322 and pBR325 are plasmids used in genetic engineering. pBR322 is an in vitro constructed cloning vehicle with ApR and TcR genes from RSF2124 and pSC101, and a replication element from pMB1. It has 40 restriction enzyme target sites but is less suitable for long DNA segments. In contrast, pBR325, a derivative of pBR322, also encodes chloramphenicol resistance along with ampicillin and tetracycline, offering expanded applications and improved vectors like pUC19 and pAT153. These plasmids have been crucial in DNA cloning and genetic engineering experiments, contributing to advancements in molecular biology research.

What is the cosmid vector:

A cosmid vector is a type of DNA carrier that includes a specific segment from a bacteriophage called lambda (ʎ). Including “Cos” site. These vectors, called cosmids, are useful for cloning large sections of foreign DNA. They work well with an in vitro packaging system to insert DNA fragments. Cosmids are especially useful for creating libraries of genetic material from eukaryotic organisms.

Write a note on RT-PCR:

RT-PCR, or Reverse Transcription Polymerase Chain Reaction, is a technique used to amplify and detect RNA molecules. It involves converting RNA into DNA using reverse transcriptase and then amplifying the DNA using PCR. RT-PCR is widely used in research, diagnostics, and forensic analysis for studying gene expression, detecting viruses, and genetic testing.

Gauecher disease:

Gaucher disease is a rare genetic disorder where glucocerebroside accumulates in cells due to a deficiency of the enzyme glucocerebrosidase. This buildup leads to organ and tissue damage. Symptoms include enlarged liver and spleen, anemia, and bone abnormalities. Enzyme replacement therapy is a common treatment.

Chemical composition of DNA:/ Note on DNA

DNA, or deoxyribonucleic acid, serves as the genetic blueprint for living organisms. Its primary function is to store, transmit, and express genetic information. DNA encodes the instructions for building and maintaining an organism's structure, controlling its growth, development, and functioning. DNA, or deoxyribonucleic acid, is composed of nucleotide units. Each nucleotide consists of a phosphate group, a deoxyribose sugar molecule, and one of four nitrogenous bases: adenine (A), thymine (T), cytosine (C), or guanine (G). The sequence of these bases forms the genetic code. Adenine pairs with thymine, and cytosine pairs with guanine through hydrogen bonds, creating the double-stranded helical structure of DNA. This unique composition allows DNA to store and transmit genetic information, playing a fundamental role in heredity and cellular processes.

Whats happen during Chromosome jumping:

During chromosome jumping, the targeted DNA is first identified, cut into fragments using restriction enzymes, and then circularized. This process facilitates the proximity of DNA sequences that were originally distant in the genome. The resulting circularized DNA fragments, originating from the closure sites, constitute a jumping library. Chromosome jumping is applied in molecular biology techniques like the cloning of genes, exemplified by the cloning of the human cystic fibrosis gene, utilizing the ability to bring together disparate DNA sequences for comprehensive genomic analysis.

How can PCR help in improving quality of environment?

1. PCR detects environmental pollutants like heavy metals and pathogens.
2. It monitors microbial diversity in various habitats.
3. PCR studies genes involved in bioremediation for effective pollutant removal.
4. Environmental DNA (eDNA) analysis identifies species presence and biodiversity.
5. PCR tracks changes in gene expression due to environmental stressors.
6. Overall, PCR aids in environmental monitoring, assessment, and management, ensuring ecosystem preservation and human health protection

Genome mapping and its type?

Assigning of a specific gene to particular region of a chromosome and determining the location of and relative distances between genes on the chromosome. There are two type here:1= Genetic Linkage Mapping: Illustrates the order and relative distances between genes or genetic markers on chromosomes. 2= Physical Mapping: Provides actual distances between landmarks on a chromosome, typically measured in base pairs.

Significant of PCR in medical field / Role of PCR in Medical:

PCR has major impact on medicine especially in the field of clinical microbiology or diagnosis. Molecular tools have also allowed to perform prenatal genetic diagnosis. PCR enables the detection of genetic disorders such as Down syndrome, cystic fibrosis, and sickle cell anemia during pregnancy.

What is biopaninng?

The primary screening method involves enriching phage clones with binding affinity for the target through a process called biopanning. Biopanning is a process used to find specific molecules, like antibodies, by enriching them from a mixture.

DNA sequence databases:

Large amounts of sequence data accumulated since the development of current DNA sequencing technology are maintained in three databases: i) National Center for Biotechnology Information ii) DNA Databank of Japan iii) European Bioinformatics Institute-UK

Eukaryotic DNA types:

1= Protein Coding Genes, 2= Tandemly Repeated Genes, 3= Repeated DNA, 4= Unclassified Spacer DNA.

Protein Coding Genes can further be classified as: 1= Duplicated and Diverged Genes, 2= Functional Gene Families and Non-functional.

Pseudogenes Tandemly Repeated Genes encode: 1= rRNA, 2= 5sRNA, 3= tRNA, 4= Histones

Multiplex and Real time PCR:

Multiplex PCR: Multiplex PCR is a variant of PCR which enables simultaneous amplification of many targets of interest in one reaction by using more than one pair of primers. The use of multiple, unique primer sets within a single PCR reaction to produce amplicons of varying sizes specific to different DNA sequences.

Real-time quantitative PCR (qPCR): qPCR is used to measure the quantity of a target sequence. It is used to measure starting amounts of DNA, cDNA, or RNA. In real-time PCR, the accumulation of amplification product is measured as the reaction progresses, in real time, with product quantification after each cycle. Q-PCR is commonly used to determine whether a DNA sequence is present in a sample and the number of its copies in the sample.

Disadvantages of RT PCR:

1= It can be costly because of needing special equipment and materials. 2= It's a bit complex to set up and analyze the data, requiring know-how. 3= It's sensitive to stuff in the samples that can mess up the results. 4= It might struggle with accurately measuring very low or high levels of stuff in the sample. 5= Making sure the data is compared fairly across different samples can be tricky. 6= It's not great at testing many things at once. 7= Sometimes, it might give wrong results if there's contamination.

Basic concept of Maxam_Gilbert DNA sequencing Method:

The Maxam-Gilbert method is a DNA sequencing technique that uses chemical reagents to break the DNA at specific bases. By inducing base-specific cleavage, this method allows researchers to determine the sequence of nucleotides in a DNA molecule.

Write a note on shotgun sequencing:

Shotgun sequencing is a method used to sequence long strands of DNA. 1= Breaking Down DNA: In shotgun sequencing, long DNA strands are broken into smaller fragments. 2= Individual Sequencing: Each fragment is sequenced individually, allowing for efficient processing. 3= Reassembly Process: After sequencing, the fragments are reassembled in their original order. 4= Efficient Genome Sequencing: This method is effective for sequencing large genomes, aiding in the study of genetics and genetic disorders.

Application of PCR:

PCR has widespread applications in various fields of life sciences including genetic engineering, medical, forensic, agriculture, environment etc.

Benefits of cDNA in recombinant DNA technology:

Here are the benefits of using cDNA in recombinant DNA technology: 1= Simplified Cloning: cDNA lacks non-coding regions, making it easier to clone genes into vectors for various applications. 2= Focused Gene Expression: It represents actively expressed genes, allowing researchers to study specific gene functions more effectively. 3= Efficient Protein Production: cDNA simplifies the process of producing proteins in host cells, as it contains only coding sequences. 4= Amplification of Low-Abundance Genes: cDNA synthesis can amplify rare or low-abundance transcripts, aiding in the study of less common genes. 5= Discovery of New Genes: cDNA libraries help in the discovery of new genes and understanding their roles in biological processes.