List of top Biology Questions on Molecular Basis of Inheritance

Student to attempt either option-(A) or (B):
(A) Write the features a molecule should have to act as a genetic material. In the light of the above features, evaluate and justify the suitability of the molecule that is preferred as an ideal genetic material. 
OR 
(B) Differentiate between the following:

  • [(i)] Polygenic Inheritance and Pleiotropy
  • [(ii)] Dominance, Codominance and Incomplete dominance
Distance between two consecutive base pairs of DNA is \rule{2cm}{0.1mm}
The flows of genetic information in central dogma are in which direction?
Which one of the following codons has dual function?
Study the items of Column-I and those of Column-II:
Column-I Column-II
(a) RNA polymerase I (i) 18s rRNA
(b) RNA polymerase II (ii) SnRNAs
(c) RNA polymerase III (iii) hnRNA
Choose the option that correctly matches the items of Column-I with those of Column-II:
The RNA triplet UAG acts as a stop codon which terminates the synthesis of a polypeptide. Below is given a strand of DNA which codes for four amino acids.
In which position will an insertion of a thymine nucleotide result in the termination of translation?
DNA strand:
3′ T C C A C C C G A T G C 5′

Construct and label a transcription unit from which the RNA segment given below has been transcribed. Write the complete name of the enzyme that transcribed this RNA.

The base sequence in one of the strands of DNA is: ‘TAGCATGAT’
  • Give the base sequence of its complementary strand.
  • How are these base pairs held together in DNA molecule?
  • Explain the base complementarity rule. Name the scientist who framed this rule.
A segment of DNA, ‘TTG AGG GGG ATG’ was translated into an oligopeptide with the amino acids, Lysine - Serine - Proline - Tyrosine.
  • [(a)] Write the codons in correct sequence for the four amino acids.
  • [(b)] If first adenine in DNA is substituted by guanine, what will be the sequence of amino acids in the new oligopeptide?
  • [(c)] Write the anticodons for these amino acids.
Assertion (A): Replication of DNA takes place in S phase of the cell cycle.
Reason (R): DNA replication and cell division cycle should be highly coordinated.
Assertion (A): A piece of DNA inserted into an alien organism generally does not replicate, if not inserted into a chromosome.
Reason (R): Chromosomes have specific sequences called ‘ori’ region, where DNA replication is initiated.
What are minisatellites?
AGGTATCGCAT is a sequence from the coding strand of a gene. What will be the corresponding sequence of the transcribed mRNA?
Removal of RNA polymerase-III from nucleoplasm of a eukaryotic cell will affect the transcription of which of the following?
The approach used in HGP of identifying all the genes that are expressed as RNA is referred to as:
In E. coli, a DNA sequence that specifies where RNA polymerase will bind and initiate transcription of a gene is:

Regulation of lac operon by repressor is referred to as:

Explain how the addition of lactose in the medium regulates the switching on of the lac operon in bacteria.

Study the given molecular structure of double-stranded polynucleotide chain of DNA and answer the questions that follow.

(a) How many phosphodiester bonds are present in the given double-stranded polynucleotide chain? 
(b) How many base pairs are there in each helical turn of double helix structure of DNA? Also write the distance between a base pair in a helix. 
(c) In addition to H-bonds, what confers additional stability to the helical structure of DNA?

The process of splicing in eukaryotes represents the dominance of the:
SNPs in Human Genome Project refers to:
Which enzyme(s) will be produced in a bacterial cell in which ‘UAG’ is inserted in the ‘lac-y gene’ due to mutation? Choose the correct option:
Isolation of DNA from a bacterial cell can be achieved by using:
The approach of sequencing the whole set of genome, including all the coding and non-coding sequences in HGP is:
The region of chromatin that are actively transcribed are thought to be: