CHAPTER – 6 : MOLECULAR BASIS OF INHERITANCE. AUG has dual functions. It functions as adapter, structural, and in some cases as a catalytic molecule. Translation process is in the 5’→3’ direction always. DNA (Deoxyribonucleic Acid) and RNA (Ribonucleic Acid) are two types of nucleic acid found in living organisms. b) Two chains have anti-parallel polarity. Dec 22, 2020 - DNA Fingerprinting - Molecular Basis of Inheritance, Biology, Class 12 | EduRev Notes is made by best teachers of NEET. It codes for methionine and also act as initiator codon. Molecular Basis of Inheritance class 12 Notes Biology. They are of 5 types – H1, H2A, H2B, H3 and H4. The genes needed only sometimes are called regulatory genes and are made to function only when required and remain non-functional at other times. 2. from the heat-killed S cells to see which ones could transform live R cells into S cells. S strain (heat-killed) → Inject into mice → Mice live, S strain (heat-killed) + R strain (live) → Inject into mice → Mice die. Download revision notes for Molecular Basis of Inheritance class 12 Notes and score high in exams. DNA, RNA and Experiments on Genetic Material; ... Molecular Basis of Inheritance Class 12 Biology Chapter 6 Notes. A phosphate group is linked to OH of 5' C of a nucleoside through phosphoester linkage to form nucleotide (or deoxynucleotide).. Nucleic acids are polymers of nucleotides. Lactose is the substrate for enzyme beta-galactosidase and it regulates switching on and off of the operon, so it is called inducer. A nucleotide consists of three elements – nitrogenous base, sugar and phosphate group. At the end release factors binds to the stop codon, terminating the translation and release of polypeptide form ribosome. Learning the important concepts is very important for every student to get better marks in examinations. Gene a encode for transacetylase. Sigma factor also help in initation of transcription .The terminator is located at 3’end of coding strand and usually defines the end of transcription where rho factor will bind to terminate transcription. ii. The strands that has polarity 3’à5 act as template and called template strand and other strand is called coding strand. (2) The length of the DNA depends on the number of nucleotide pairs present in it. • Nucleic acids are the macromolecules present in all living cell. e) Repetitive sequences are stretches of DNA sequences that are repeated many times, sometimes hundred to thousand times. A nucleotide consists of three elements – nitrogenous base, sugar and phosphate group. g) Scientists have identified about 1.4 million locations where single base DNA differences (SNPs – single nucleotide polymorphism) occur in humans. A phosphate group is linked to OH of 5' C of a nucleoside through phosphoester linkage to form nucleotide (or deoxynucleotide).. i. Molecular Basis Of Inheritance Cbse Notes For Class 12 by learncbse.in. 13. e) The plane of one base pair stacks over the other in double helix to confer stability. Polymorphism in DNA sequence is the basis for genetic mapping of human genome as well as fingerprinting. After that, Mendel’s experiment the theory of inheritance. t-RNA is specific for each amino acids. This is known as frameshift mutation. OVERVIEW: LIFE’S OPERATING INSTRUCTIONS • In 1953, James Watson and Francis Crick introduced an elegant double-helical model for the structure of deoxyribonucleic acid, or DNA • DNA, the substance of inheritance… Download CBSE Class 12 Biology Molecular Basis Of Inheritance Notes Set A in pdf, Biology chapter notes, class notes mind maps formulas Revision Notes CBSE Class 12 Biology - Molecular Basis Of Inheritance. Structure of DNA: Watson and Crick proposed a double helical model for DNA, based on X-ray crystallography of the molecule. So, DNA is better genetic material. MCQs. NCERT Class 12 Biology Chapter 6 Molecular Basis of Inheritance Revision Notes contains very easy language which helps the students to study and revise syllabus with almost no time. ... 12. This section describes this whole process in details, as it is a process of biological inheritance. According to the central dogma of molecular biology, the genetic information flows from DNA to RNA to Protein. • Transcription of DNA includes a promoter, the structural gene and a terminator. The m-RNA provide the template, t-RNA brings the amino acids and read the genetic code, the r-RNA play structural and catalytic role during translation. In prokaryotes, well defined nucleus is absent and negatively charged DNA is combined with some positively charged proteins called nucleoids. It is the process of copying genetic information from one strand of DNA into RNA. Molecular Basis of Inheritance CBSE Class 12-science Biology Revision Notes for Molecular Basis of Inheritance From learning radioactive wastes and genetics to understanding food production and reproductive health, your Class 12 Science syllabus for Biology introduces you to a wealth of information. DNA Strand with 5′ {tex}\to {/tex} 3′ Polarity, Acts as template for transcription and codes for RNA. Rajkumar Biology: A guide for 11th & 12th CBSE Students. Adenine on DNA binds to uracil on the new RNA strand being created. (b) RNA contains cytosine and uracilpyrimidine bones and guanine and adenine as purine bases. The order and sequence of amino acids are defined by the sequence of bases in the mRNA. translation, Gene expression is regulated by environmental, physiological and metabolic conditions, The development and differentiation of embryo is a result of coordinated regulation and expression of several sets of genes, Control of gene expression in prokaryotes is mainly at the initiation of transcription, The activity of RNA polymerase at the start site is regulated by regulatory proteins, which can be a repressor or activator, The accessibility of the promoter region is regulated by an operator sequence adjacent to it, that binds with the specific protein, mostly a repressor. d) Repeated sequences make up very large portion of the human genome. • Freidrich Miescher was the first person isolated the nucleic acids from the pus cells. Exons are those sequences that appear in mature and processed RNA. DNA acts as genetic material in most of the organisms. 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