Q
Who discovered nucleic acids ?
Friedrich Miescher
What type of linkage holds together the monomers of DNA and RNA?
Phosphodiester linkage
What are the different types of RNA found in the cell?
m-RNA, r-RNA, t-RNA, mi-RNA, si-RNA
Who discovered DNA ?
James Watson and Francis Crick
Which nucleic acid is responsible for carrying out protein synthesis in the cell?
Ribonucleic Acid (RNA)
To which of the following does thymine form hydrogen bonds in DNA?
Adenine
Nucleoside is composed of:
Pentose sugar and base
State the use of tRNA.
Brings specific amino acids to the ribosome / acts
as an adapter molecule.
The two strands in DNA double helix are joined by ______________ bonds.
Hydrogen
What is the number of carbon atoms in a dinucleotide?
Ten
A pairs with T via __ H-bonds, G pairs with C via __ H-bonds in DNA.
a) 3,2
b) 3,3
c) 3,1
d) None of the above
d) None of the above
What is the difference between Purines and Pyrimidines?
Purines are bicyclic compounds and Pyrimidines are monocyclic compounds.
What is common feature of Uracil and Thymine ?
Both are Pyrimidines.
RNA contains
(a) ribose sugar and thymine
(b) ribose sugar and uracil
(c) deoxyribose sugar and uracil
(d) deoxyribose sugar and thymine
(b) ribose sugar and uracil
Assertion: DNA undergoes replication.
Reason: DNA contains cytosine and thymine as pyrimidine base.
(b) Assertion is true, Reason is true; Reason is not a correct explanation for Assertion
Which RNAs regulate gene expression ?
miRNA, siRNA
Which of the following statements is NOT true?
a) Sugar component of a nucleotide is ribose.
b) Sugar component of a nucleotide is deoxyribose.
c) The bases in nucleotides are attached to a pentose sugar moiety by a phosphodiether linkage.
d) The sugar molecule of the nucleotide is in L-configuration.
c) The bases in nucleotides are attached to a pentose sugar moiety by a phosphodiether linkage.
Dinucleotide is obtained by joining two nucleotides together by phosphodiester linkage. Between which carbon atoms of pentose sugars of nucleotides are these linkages present?
a) 5′ and 3′
b) 1′ and 5′
c) 5′ and 5′
d) 3′ and 3′
a) 5′ and 3′
When RNA is hydrolysed, there is no relationship among the quantities of different bases obtained. What does this fact suggest about the structure of RNA?
A DNA molecule is double-stranded in which the pairing of bases occurs. Adenine always pairs with thymine, while cytosine always pairs with guanine.
Therefore, on hydrolysis of DNA, the quantity of adenine produced is equal to that of thymine and similarly, the quantity of cytosine is equal to that of guanine.
But when RNA is hydrolyzed, there is no relationship among the quantities of the different bases obtained. Hence, RNA is single-stranded.