AP BIOLOGY

THE MOLECULAR BASIS OF INHERITANCE

DNA REPLICATION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
Which of these enzymes is responsible for breaking the hydrogen bonds which “unzips” the DNA molecule?
A
Topoisomerase
B
Primase
C
Helicase
D
zippase
Explanation: 

Detailed explanation-1: -Key enzyme involved in DNA replication, it is responsible for ‘unzipping’ the double helix structure by breaking the hydrogen bonds between bases on opposite strands of the DNA molecule.

Detailed explanation-2: -Abstract. Helicases are essential enzymes involved in all aspects of nucleic acid metabolism including DNA replication, repair, recombination, transcription, ribosome biogenesis and RNA processing, translation, and decay.

Detailed explanation-3: -Helicases are enzymes that bind and may even remodel nucleic acid or nucleic acid protein complexes. There are DNA and RNA helicases. DNA helicases are essential during DNA replication because they separate double-stranded DNA into single strands allowing each strand to be copied.

Detailed explanation-4: -DNA helicases are molecular motors. Through conformational changes caused by ATP hydrolysis and binding, they move along the template double helix, break the hydrogen bonds between the two strands and separate the template chains, so that the genetic information can be accessed.

Detailed explanation-5: -DNA helicases are enzymes that are able to unwind DNA by the use of the energy-equivalent ATP. They play essential roles in DNA replication, DNA repair, and DNA recombination in all organisms.

There is 1 question to complete.