Chemical basis of heredity is?
DNA
RNA
Histones
None
Related Questions
Statements
I. The four nucleotide bases are not necessarily present in DNA in exact equal
proportions.
II. The total amount of purines are equal to the total amount of pyrimidines.
III. DNA ligase enzyme act to hydrolyse or breakdown a polynucleotide chain into
its component nucleotides.
IV. Nuclease enzymes are capable of restoring an intact DNA duplex.
Of the above statements
II is correct, but I, III and IV are wrong
I and II are wrong but III and IV are correct
I, II and III are correct but IV is wrong
I and II are correct but III and IV are wrong
Choose the incorrect statement w.r.t. structure of DNA proposed by Watson and Crick.
Watson-Crick structure is also known as B form of DNA
The two anti-parallel polynucleotide chains in the structure given by Watson and Crick are not identical in either base sequence or composition, rather they are complementary to each other
Each nucleotide base of one strand is paired with the base of another strand in which adenine pairs with thymine and guanine pairs with cytosine
Adenine pairs with thymine by three hydrogen bonds and guanine pairs with cytosine by two hydrogen bonds
Purines posses nitrogen at
1, 2, 4 and 6 positions
1, 3, 5 and 7 positions
1, 3, 7 and 9 positions
1, 2, 6 and 8 positions
Histones are rich in the basic amino acid residues like?
Lysine
Methionine
Arginine
Both 1 and 3
Which of the following is structural subunit of DNA?
Protein
Carbohydrate
RNA
Nucleotides
In DNA of certain organisms, guanine constitutes 20% of the bases. What percentage of the bases would be adenine?
0%
0.1
0.2
0.3
If the distance between two consecutive base pairs is nm and the total number of base pairs of a DNA double helix in a typical mammalian cell is bp, then the length of the DNA is approximately:
2.2 m
2.0 m
2.5 m
1.8 m
An analysis of a DNA (double strandard) sample yielded 18% cytosine. What would be the percentage of other bases in this sample?
T- 32%, A-32%, G-18%
T-32%, A-18 %, G-32%
T-18%, A-32%, G-32%
T-40%, A-22%, G-20%
Number of base pairs of DNA helix in a typical nucleosome?
200
100
500
2000
A bacterial chromosome has base pairs. Calculate the approximate length of this chromosome in micrometers, given that the distance between base pairs is 0.34 nm.
1564 micrometers
1.564 micrometers
4.6 micrometers
0.34 micrometers
