Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
18 Cards in this Set
- Front
- Back
- 3rd side (hint)
|
Helicase (3 parts) |
Reads DNA site where bubble starts Latches on and untwists helix Separates helix Unwinds and separates parental DNA strands |
Helix |
|
|
Single Strand Binding Protein |
Keeps the fork open and stable Binding proteins stabilizes the unwound parental strands |
|
|
|
RNA Primer |
RNA nucleotides that start a leading or lagging strand Made by primase enzyme |
|
|
|
DNA Polymerase III |
Makes the polynucleotide Continues growth of RNA primer, but with DNA nucleotides Cannot add nucleotides without primer Adds nucleotides to the primer, forming Ukazaki fragments |
|
|
|
Topoisomerase |
In in front of each fork - not part of replisome complex Relieves mechanical stress: breaks sugar binding and the DNA coils up, and then rebinds the sugars It breaks, swivels, and rejoins the parental DNA ahead of the replication fork, relieving the strain caused by unwinding |
|
|
|
Okazaki Fragments |
Lagging strand Short segments from DNA replication |
|
|
|
Lagging Strand |
Made up of Okazaki Fragments, made from 5' to 3' end |
|
|
|
Leading Strand |
Made continously 3' to 5' direction |
|
|
|
DNA Polymerase I |
Locates primers Replaces them with DNA nucleotides Replaces RNA with DNA, adding to the 3' end |
|
|
|
DNA Ligase |
Forms bonds between the sugar phosphate backbones of the new DNA nucleotides (from the replaces RNA nucleotides) and the DNA nucleotide strand made from Polymerase III |
|
|
|
Why do we have telomeres? |
To stop chromosomal erosion (Lagging strand synthesis could cause loss of gene which could be important - we cannot remove the primers at the end)
Everytime a cell replicates, parts of the telomeres are lost and the genetic component that needs to be kept safe isn't damaged |
|
|
|
Telomeres... somatic and germ cells |
Somatic cells telomeres shorten as we get older, but the germ cells (eggs and sperm) and cancer cells stay the same. |
|
|
|
Telomerase |
It rebuilds telomerase for some cancers and gamete. The DNA strand serving as the template for the "lagging strand" is extending by repeating nonsense nucleotides (added on by the telomerase). |
|
|
|
What happens with mistakes in nucleotide sequence |
Each new strand of DNA is proofread and mistakes are corrected by special enzymes |
|
|
|
What do the family of nuclear energy or ensonuclease |
•Find problems in replication•Cut sugar-phosphate backbone on either side of error•1 family of Polymerase adds nucleotides in correct order •Ligase reconnects backbone |
|
|
|
What are telomeres? |
They are relatively large pieces of nonsense nucleotides that do not code for a gene. During cell replication we lose a section of them. |
|
|
|
Primase |
Primase synthesizes RNA primers, using the parental DNA as a template |
|
|
|
Parts of Replisome Complex |
Helicase Primase (Primer) Single-Strand Binding Protein DNA Polymerase III (and Sliding Cramp) |
|
