10 Questions
Shown below is a replication bubble. At which location is the DNA polymerase adding nucleotides in a continuous manner?
A and D
What is the name of the DNA sequence where replication begins?
replication origin
What is the function of a topoisomerase in DNA replication?
It relieves the tension in DNA strands.
How does Polymerase help maintain the accuracy of DNA replication?
DNA polymerase can cut out improperly base-paired nucleotides and add the correct one during synthesis.
The bonds that link two DNA strands together are
hydrogen bonds.
The sequence at which DNA replication begins tends to have which characteristic?
AT-rich
Which double-strand break repair mechanism is a simple ligation mechanism?
nonhomologous end joining
How are the primers from which DNA synthesis starts different from the DNA itself?
The primers are made up of RNA not DNA.
If a stretch of DNA on the parental strand of a replicating chromosome has the sequence 5′–AGCTCGATCGGCTA–3′, what will the sequence of the newly synthesized strand made from this stretch of template be?
3′–TCGAGCTAGCCGAT–5′
The energy for the polymerization reaction in DNA synthesis is powered by
the breaking of high-energy phosphate bonds in the deoxynucleotides.
Study Notes
Replication Bubble
- DNA polymerase adds nucleotides in a continuous manner at the leading strand.
Origin of Replication
- Replication begins at a specific DNA sequence called the origin of replication.
Topoisomerase
- Topoisomerase relaxes the tension in the DNA double helix that builds up ahead of the replication fork by cutting and rejoining the DNA strands.
Polymerase Accuracy
- Polymerase maintains the accuracy of DNA replication by proofreading and editing its work, correcting any errors that occur during DNA synthesis.
DNA Strand Bonds
- The bonds that link two DNA strands together are hydrogen bonds.
Origin of Replication Characteristics
- The sequence at which DNA replication begins tends to have a characteristic of being rich in adenine (A) and thymine (T) bases.
Double-Strand Break Repair
- The simple ligation mechanism of double-strand break repair is non-homologous end joining (NHEJ).
Primers
- Primers from which DNA synthesis starts are different from the DNA itself in that they are short RNA molecules, typically 10-12 nucleotides in length, that provide a free 3' hydroxyl group for DNA synthesis to begin.
DNA Synthesis
- If a stretch of DNA on the parental strand of a replicating chromosome has the sequence 5′–AGCTCGATCGGCTA–3′, the sequence of the newly synthesized strand made from this stretch of template will be 3′–TCGAGCTAGCCAT–5′.
Energy for Polymerization
- The energy for the polymerization reaction in DNA synthesis is powered by the hydrolysis of high-energy phosphate bonds in nucleotide triphosphates (dNTPs).
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
