Structure of DNA
The areas where DNA separates during replication is...
Replication forks.
What happens last in DNA replication?
Two new DNA molecules form.
DNA is replicated before...
Cell division or mitosis.
Mitosis is?
Cell division.
When does the replication occur?
Replication occurs before the begins mitosis.
Replication forks tend to...
Speed up replication.
Base-pairing rules
The adenine (purine) bonds with thymine (pyrimidine), and Guanine (purine) pairs with Cytosine (pyrimidine) through hydrogen bonds.
Complementary
The pairs A&T plus G&C are complementary towards each other.
How do photographs help in Wilkins & Franklin's discovery of the structure of DNA?
The picture (X-ray) along with many other calculations determined the shape to be the helix of 2 chains of nucleotides.
What is replication?
The process of making a copy of DNA.
What are the purines?
The purines are Adenine & Guanine.
Watson & Crick deduce about the structure of DNA?
They used the information from Chargaff, Franklin, & Wilkins to construct their DNA model.
What are the pyrimidines?
Thymine & Cytosine.
At the end of replication, each new DNA molecule is composed of...
A new and original strand of DNA.
Chargaff's discovery...
Adenine always pairs with thymine and guanine always bonds with cytosine. (Chargaff's Rule).
The 4 nitrogen bases...
Adenine, thymine, guanine, & cytosine.
What must occur before the replication can begin?
Before the process begins the double helix must unwind.
Adenine and Guanine are...
Bigger bases connected to H-bonds, while thymine and Cytosine are smaller.
What proofreads the new DNA molecules during replication?
DNA Polymerases.
DNA Helicase...
Enzyme that opens the double helix by BREAKING hydrogen bonds between nitrogen bases.
DNA Polymerases...
Enzymes that move along each of the DNA strands during replication, adding nucleotides.
DNA Helicases and DNA polmerases are alike in that both are...
Enzymes.
Why are there sometimes 3 H-bonds and then sometimes 2 H-bonds?
Guanine and cytosine tend to create 3 H-bonds while adenine and thymine create 2 H-bonds.
What do the lines that connect the two strands represent?
Hydrogen Bonds.
At the end of replication, each new DNA molecule is...
Identical.
Adenine, thymine, guanine, & cytosine are...
Nucleotides named by the nitrogen base which is attached to sugar. (And are complementary)
DNA Replication...
Process of making copies of DNA.
Suppose that a strand of DNA has the base sequence ATT-CCG. What is the base sequence of the complementary strand?
TAA-GGC.
