This energy comes from the nucleotides themselves, which have three phosphates attached to them (much like the energy-carrying molecule ATP). When the bond between phosphates is broken, the energy released is used to form a bond between the incoming nucleotide and the growing chain.
What is the source of energy for DNA replication?
The energy for this process of DNA polymerization comes from hydrolysis of the high-energy phosphate (phosphoanhydride) bonds between the three phosphates attached to each unincorporated base .
Where does energy for DNA replication come from quizlet?
Energy for DNA polymerization during replication is derived from: hydrolysis of the high-energy phosphate bond between the α phosphate and β phosphate of the nucleotide newly incorporated into the growing DNA strand .
Does DNA replication take energy?
During DNA replication, DNA helicases unwind DNA at positions called origins where synthesis will be initiated. ... The process of breaking the hydrogen bonds between the nucleotide base pairs in double-stranded DNA requires energy .
Where does energy come from to create growing strand?
The addition of a nucleotide to the new DNA strand is catalyzed by an enzyme (DNA polymerase), which cleaves off two phosphate groups from the end of the nucleotide. This releases enough energy to link the nucleotide to the 3′ end of the growing DNA strand.
What are the 4 energy forms that are used in DNA replication?
These are dATP, dGTP, dTTP and dCTP . The high energy phosphate bond between the a and b phosphates is cleaved and the deoxynucleotide monophosphate is incorporated into the new DNA strand. Ribonucleoside triphosphates (NTP’s) are also required to initiate and sustain DNA synthesis.
What are the three major requirements of replication?
Replication occurs in three major steps: the opening of the double helix and separation of the DNA strands, the priming of the template strand, and the assembly of the new DNA segment . During separation, the two strands of the DNA double helix uncoil at a specific location called the origin.
What is the role of Okazaki fragments in DNA replication?
Okazaki fragments are short sequences of DNA nucleotides (approximately 150 to 200 base pairs long in eukaryotes) which are synthesized discontinuously and later linked together by the enzyme DNA ligase to create the lagging strand during DNA replication.
What does DNA polymerase use as its energy source?
The process uses a complementary, single strand of DNA as a template. The energy required to drive the reaction comes from cutting high energy phosphate bonds on the nucleotide-triphosphate’s used as the source of the nucleotides needed in the reaction.
What are the 3 theories of DNA replication?
There were three models for how organisms might replicate their DNA: semi-conservative, conservative, and dispersive .
What are the 5 steps in DNA replication?
- Step 1: Replication Fork Formation. Before DNA can be replicated, the double stranded molecule must be “unzipped” into two single strands.
- Step 2: Primer Binding. The leading strand is the simplest to replicate.
- Step 3: Elongation.
- Step 4: Termination.
Where does DNA replication happen?
DNA replication occurs in the cytoplasm of prokaryotes and in the nucleus of eukaryotes . Regardless of where DNA replication occurs, the basic process is the same. The structure of DNA lends itself easily to DNA replication.
What is the leading strand in DNA replication?
The leading strand is a single DNA strand that, during DNA replication, is replicated in the 3′ – 5′ direction (same direction as the replication fork). DNA is added to the leading strand continuously, one complementary base at a time.
Why is there a need to produce Okazaki fragments?
Why is there a need to produce Okazaki fragments on the lagging strand, but not on the leading strand of DNA? -By having one leading strand and one lagging strand the cell can limit the amount of DNA polymerase used for chromosomal replication . -The leading strand opens first, and so Okazaki fragments are not needed.
Why are Okazaki fragments necessary?
Okazaki fragments are necessary for the replication of both strands simultaneously . As DNA polymerase can only add nucleotides in 5’→3′ direction of the growing strand, the lagging strand has to be synthesized discontinuously away from the replication fork.
Which is the lagging strand?
The lagging strand is the DNA strand replicated in the 3′ to 5′ direction during DNA replication from a template strand . It is synthesized in fragments. ... The discontinuous replication results in several short segments which are called Okazaki fragments.
