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प्रश्न
Which property of DNA double helix led Watson and Crick to hypothesise semi-conservative mode of DNA replication? Explain.
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उत्तर
Watson and Crick proposed a semi-conservative mode of DNA replication based on the molecule’s antiparallel, double-stranded structure. They suggested that the two strands of the DNA molecule uncoil and separate, with each strand serving as a template for the production of a new (complementary) strand alongside it. The template and its complement then combine to generate a new double-stranded DNA molecule identical to the original. The sequence of bases that should be present in the new strands is easily predicted because they will be complementary to the bases present in the old strands. A will partner with T, T with A, C with G, and G with C. As a result, two daughter DNA molecules are created that are identical to the parent molecule; each daughter DNA molecule consists of one new and one old strand. This replication mechanism is referred to as semi-conservation because each daughter molecule contains only one conserved parent strand. Later, experiments by Joseph Taylor, Meselson and Stahl verified it.
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संबंधित प्रश्न
Chargaff’s rules are applicable to ______.
One turn of DNA possesses ______.
A nucleoside differs from a nucleotide. It lacks the ______.
The fact that a purine base always paired through hydrogen bonds with a pyrimidine base leads to, in the DNA double helix ______.
Who amongst the following scientists had no contribution in the development of the double helix model for the structure of DNA?
Protein helping in opening of DNA double helix in front of replications fork is ______.
Synthesis of DNA from RNA is explained by ______.
H-bonds between Cytosine and Guanine are ______.
By which bonds the purine and pyrimidine pairs of Complementary Strands of DNA held together?
DNA is made of two chains that twist about one another in the shape of a ______.
Which of the following is a structural subunit of DNA?
A peptide chain assumes secondary structure through the formation of ______.
A short piece of DNA, having 20 base pairs, was analyzed to find the number of nucleotide bases in each of the polynucleotide strands. Some of the results are shown in the table.
| Number of nucleotide bases | ||||
| Adenine | Cytosine | Guanine | Thymine | |
| Strand 1 | 4 | 4 | ||
| Strand 2 | 5 | |||
How many nucleotides containing Adenine were present in strand 2?
A nucleotide is the monomer unit of a nucleic acid. Which of the following correctly identifies the three components of a nucleotide?
Which of the following nitrogenous bases is classified as a purine with a double-ring structure?
The phosphate group in a nucleotide is attached to which carbon of the pentose sugar?
In a polynucleotide chain, nucleotides are linked together by which type of bond?
The backbone of a polynucleotide chain is formed by which components?
In a DNA double helix, what is the spatial relationship between the two polynucleotide strands?
In a DNA double helix, where are the nitrogenous bases located?
What is the significance of the 2′-OH group in ribose compared to deoxyribose?
A dinucleotide is formed by linking two nucleotides together. The bond formed between them is:
A nucleotide is the monomer unit of a nucleic acid. Which of the following correctly identifies the three components of a nucleotide?
What structural difference exists between the pentose sugar found in DNA and the pentose sugar found in RNA?
The phosphate group in a nucleotide is attached to which carbon of the pentose sugar?
What type of bond connects a nitrogenous base to the pentose sugar in a nucleotide?
In a polynucleotide chain, nucleotides are linked together by which type of bond?
A dinucleotide is formed by linking two nucleotides together. The bond formed between them is:
