Molecular Basis of Inheritance MCQs for NEET — Botany Questions with Answers

The NCERT text states: 'If a germ cell mutation does not seriously impair individual’s ability to have offspring who can transmit the mutation, it can spread to the other members of population (through sexual reproduction).'

The steps mention: '(iv) transferring (blotting) of separated DNA fragments to synthetic membranes, such as nitrocellulose or nylon'.

The text states: 'Further, as the polymorphisms are inheritable from parents to children, DNA fingerprinting is the basis of paternity testing, in case of disputes.'

The NCERT text says: 'These repetitive DNA are separated from bulk genomic DNA as different peaks during density gradient centrifugation... Depending on base composition (A : T rich or G:C rich), length of segment, and number of repetitive units, the satellite DNA is classified into many categories...'

The NCERT text defines a DNA polymorphism: 'Allelic... sequence variation has traditionally been described as a DNA polymorphism if more than one variant (allele) at a locus occurs in human population with a frequency greater than 0.01.'

The NCERT text states: 'He proposed that the ‘factors’ (later named as genes) regulating the characters are found in pairs known as alleles.' and 'After knowing that the genes are located on the chromosomes, a good correlation was drawn between Mendel’s laws: segregation and...' This directly indicates that Mendel's 'factors' were later identified as genes located on chromosomes.

The text states: 'However the nature of those ‘factors’ which determine the phenotype was not very clear. As these ‘factors’ represent the genetic basis of inheritance, understanding the structure of genetic material and the structural basis of genotype and phenotype conversion became the focus of attention in biology for the next century.' This clearly indicates that the unclear nature of the 'factors' led to the search for genetic material.

The text lists Watson, Crick, Nirenberg, Khorana, Kornbergs (father and son), Benzer, Monod, Brenner as major contributors to molecular biology after Mendel. Mendel's work preceded and laid the foundation for the 'Search for Genetic Material', but he himself is not mentioned as a molecular biologist who contributed after this search began.

The text explicitly states: 'The entire body of molecular biology was a consequent development with major contributions from Watson, Crick, Nirenberg, Khorana, Kornbergs (father and son), Benzer, Monod, Brenner, etc.' This directly links the understanding of genetic material structure to the rise of molecular biology.

The text states: 'Mendel proposed the principles of inheritance, which are today referred to as ‘Mendel’s Laws of Inheritance’. He proposed that the ‘factors’ (later named as genes) regulating the characters are found in pairs known as alleles.' This summarizes Mendel's key contribution.