Bonding across the double hellx Why is it an advantage for the two strands of th
ID: 257218 • Letter: B
Question
Bonding across the double hellx Why is it an advantage for the two strands of the DNA double helix to be held together using hydrogen bonds rather than covalent bonds? Multiple Choice Covalent bonding across the double helitx would make the DNA less stable than hydrogen bonding across the double helx. Covalent bonds would not allow bases to pair according to Chargaffs rules. There are no enzymes that are capable of forming covalent bonds across the double heltix Covalent bonds would be too strong to allow the two strands of the double heltx to easlly separate. Covalent bonds are energetically too expensive to produce.Explanation / Answer
Q.1
Option 4.
Covalent bond would be too strong to allow the two strands of the double helix to easily separate. Double stranded DNA often denature and re-anneal for replication and transcription purpose. Hence, it is an advantage for the dsDNA helix to be held together using hydrogen bonds rather than the covalent bond.
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Q.2
Option 2.
5’ – T A G A C – 3’
3’ – A T C T G – 5’
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Q.3
Option 3.
Lagging strand consist of Okazaki fragments. These fragments of DNA are ligated with the help of DNA ligase. When the production of DNA ligase is much less than the normal then the DNA replication would occur, but replication of the lagging strand would take much longer than the normal.
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Q.4
Option 5.
Nucleotides within DNA are composed of phosphate group, deoxyribose sugar, and nitrogenous base (Adenine, Guanine, Cytosine, and Thymine).
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Q.5
Option 4.
DNA consist of Adenine, Guanine, Cytosine and Thymine.
RNA consist of Adenine, Guanine, Cytosine and Uracil.