AP BIOLOGY

THE MOLECULAR BASIS OF INHERITANCE

DNA REPLICATION

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
What is responsible for preventing the opened DNA strands from reannealing?
A
Topoisomerase
B
Okazaki Fragments
C
Single Stranded Binding Proteins
D
Primase
Explanation: 

Detailed explanation-1: -The replication forks are the actual site of DNA copying. During replication within the fork, helix destabilizing proteins, called single stranded binding proteins (SSB), bind to the single-stranded regions preventing the strands from rejoining.

Detailed explanation-2: -Abstract. Single-stranded DNA (ssDNA) binding protein plays an important role in the DNA replication process in a wide range of organisms. It binds to ssDNA to prevent premature reannealing and to protect it from degradation.

Detailed explanation-3: -This is done by single strand binding protein, or SSB protein, which binds to the unpaired single-stranded DNA and prevents the two parental strands from reannealing.

Detailed explanation-4: -Single-stranded DNA-binding protein (SSB) binds to single-stranded regions of DNA (ssDNA) to protect it from annealing, prevention of secondary structure formation and digestion.

Detailed explanation-5: -Single-strand binding proteins coat the DNA around the replication fork to prevent rewinding of the DNA. Topoisomerase works at the region ahead of the replication fork to prevent supercoiling. Primase synthesizes RNA primers complementary to the DNA strand.

There is 1 question to complete.