question_answer 1)

Briefly describe the following : (a) Transcription (b) Polymorphism (c) Translation (d) Bioinformatics  

Answer:

(a) Transcription is the process of copying information from one of the strands of DNA to assemble RNA that is required for the synthesis of proteins. RNA is assembled simply based on complementrity of the DNA strand, only uracil is substituted in place of thymine. Only a small segment of DNA that codes for a polypeptide is copied. (b) Polymorphism. Polymorphism (variation at genetic level) appears due to mutations. The sequences which donot code for any proteins constitute bulk of human genome. Such sequences exhibit plenty of polymorphism. DNA from tissues like skin, bone, saliva, sperm, blood, hair follicle represent same type of polymorphism is responsible for forming the basis of DNA finger printing. Paternity testing can be carried out by DNA finger printing because polymorphism is transmitted from parents to offspring. Allelic sequence variation is called as DNA polymorphism if one allele or variant at a locus is found in human population with a frequency higher than 0.01. (c) Translation is the process of polymerization of polypeptide chain using mRNA as a template, with the help of ribosomal units. The sequence of amino acids is dictated by the sequence of triplet codons on the mRNA transcript. (d) Bioinformatics is a computer-assisted interdisciplinary science which deals with acquisition, storage, management, access and processing of molecular biological data. The term Bioinformatics is derived from two words: "Biology" and "Informatics" so bioinformatics concerns the creation and maintenance of databases of biological information’s. It involves the application of computer science and information technology to analyse and manage biological data. The majority of such databases are in the form of nucleic acid sequences and the protein sequences derived from them. These databases are very essential for current and future biotechnology research. In the last few decades, advances in molecular biology and computer technology have led to rapid sequencing of large portions of genomes of several species and are responsible for the revolution in bioinformatics. Thus two main components of bioinformatics are: (i) Computational biology refers to development of algorithmic tools to develop DNA sequences of various organisms; structure and function of RNA sequences and protein sequences; clustering protein sequences into families of related sequences and the development of protein models; and aligning similar proteins and generating phylogenetic trees to examine evolutionary relationship. So computational biology helps in analysis and interpretation of biological data. (ii) Bioinformatics infrastructure comprises the development of the entire array of information management systems, analytical tools and communication networks which support biology. Aims of bioinformatics • To spread scientifically investigated knowledge for the benefit of the research community • To transform the biological polymeric sequences into sequences of digital symbols and to store them as databases. • To develop a variety of methods and tools of software for data analysis.