Term
| Where does replication start? |
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Definition
| At the origin of replication |
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Term
| How many ORIs per chromosome? |
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Definition
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Term
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Definition
| All of the DNA replicated from a single ORI |
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Term
| What are origins of replications (ORIs)? |
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Definition
| Specific sites where DNA unwinding and initiation of replication begins |
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Term
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Definition
| Cis-acting DNA sequences required to initiate replication. Includes DNA elements that facilitate unwinding. |
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Term
| What does "cis-acting" mean? |
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Definition
| A cis-acting DNA sequence is directly adjacent to the DNA target. |
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Term
| Speaking about replicators, is it easier for them to start unwinding DNA in A-T rich areas or G-C rich ones? |
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Definition
| A-T rich areas because it is easier to separate the bonds. (2 hydrogen bonds instead of 3 as in G-C) |
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Term
| Are ORIs part of the replicator sequence? |
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Definition
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Term
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Definition
| Initiators recognize DNA elements in a replicator and initiate replication. |
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Term
| Are initiators sequence specific? |
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Definition
| Often, yes, but not always. Especially likely to be sequence specific in prokaryotes. |
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Term
| True or false: There is one initiator binding site per replicator. |
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Definition
| False. Multiple initiator binding sites per replicator. |
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Term
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Definition
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Term
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Definition
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Term
| When does DnaA bind to ds 9-mer vs. 13-mer? |
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Definition
| DnaA binds to 9-mer when DnaA is not bound to ATP. When DnaA is bound to ATP, it can bind to either 9-mer or 13-mer |
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Term
| What protein does DnaB recruit? |
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Definition
| Each DnaB recruits a primase |
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Term
| What causes DnaC release? |
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Definition
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Term
| What causes DnaB activation? |
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Definition
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Term
| During replication, which starts first, leading strand synthesis or lagging strand? |
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Definition
| Leading strand synthesis starts first. |
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Term
| What does DNA polymerase recognize during replication? |
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Definition
| Primer:template junction on leading strand. |
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Term
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Definition
| Linking of daughter genomes. Occurs in the process of replication in prokaryotes. |
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Term
| What decatenanates linked daughter genomes in prokaryotes? |
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Definition
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Term
| Are replicators in multicellular organisms sequence specific? |
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Definition
| Likely not, but replicators in multicellular organisims are not well understood. |
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Term
| How many times does initiation of replication happen in eukaryotes per cell cycle? |
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Definition
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Term
| Initiation of replication in eukaryotes is dependant on what protein? |
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Definition
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Term
| Which phase of the cell cycle includes helicase loading? |
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Definition
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Term
| During what phase of the cell cycle to protein kinases activate helicases? |
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Definition
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Term
| What is the function of protein kinases? |
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Definition
| Protein kinases add phosphates to proteins in order to turn them on. |
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Term
| Is helicase loading and activation ATP dependent? |
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Definition
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Term
| During what phase of the cell cycle are CDK levels low? |
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Definition
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Term
| What do CDK proteins affect helicase? |
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Definition
| CDK inhibits helicase loading and assists with helicase activation. |
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Term
| Inactive helicases loaded at an ORI are removed how? |
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Definition
| By a passing replication fork. |
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Term
| What does CDK stand for and what is it's general function? |
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Definition
| Cyclin Dependent Kinases add phosphates to proteins to turn them on. |
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Term
| How are replicators in daughter cells of eukaryotes inactivated? |
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Definition
| CDK inhibits helicase loading. A helicase needs to be added and activated before replication can start. |
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Term
| Which had linear genomes, eukaryotes or prokaryotes? |
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Definition
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Term
| What is an "end replication problem"? |
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Definition
| Due to eukaryotes linear genome, the end primer on the last Okazaki fragment can be removed but no DNA can be added because DNA needs a 3' end |
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Term
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Definition
| Short pieces of DNA that protect chromosome ends. They do not code for anything. |
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Term
| What is responsible for limiting the number of times a cell can divide? |
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Definition
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Term
| About how many time can a cell divide and what happens when it divides more times? |
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Definition
| Because of the length of telomeres, a cell can divide about 20 times and then the telomeres are too short and the cell undergoes apoptosis. |
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Term
| What enzyme allows stem cells and embryonic cells to replicate so many more times than normal cells? How does it function? |
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Definition
| Stem cells and embryonic cells express the enzyme telomerase which stops the shortening of telomeres by extending the 3' end out past the 5' end creating an overhang. |
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Term
| How does telomerase function specifically? |
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Definition
| Telomerase has polymerase activity. It adds a very specific sequence of bases over and over again in the same order. |
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Term
| Why did everything think Dolly died and why did Dolly actually die? |
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Definition
| Original thought was short telomeres cause by cloning caused her death. Actually, she died due to cancer contracted from a virus that infected the lab. |
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Term
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Definition
| The removal of a nucleus from its cell. |
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Term
| Dolly is a clone of what sheep species? |
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Definition
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|
Term
| What kind of cell donated the genetic material for Dolly? |
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Definition
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Term
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Definition
| A substitution base switch from a pyrimidine to a pyrimidine or a purine to a purine. |
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Term
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Definition
| A substitution base switch from pyrimidine to purine or vice versa. |
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Term
| Substitution mutations cause what kind of mutations? |
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Definition
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Term
| What is a silent mutation? |
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Definition
| A mutation that does not alter protein function. |
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Term
| What is a missense mutation? |
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Definition
| A mutation that produces a different amino acid. This results in a protein that has anywhere from none to almost total function. |
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Term
| What is a nonsense mutation? |
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Definition
| A mutation that specifies a stop codon where there was originally an amino acid. Depending on where this occurs, the protein may still be partially functional. |
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Term
| What causes frameshift mutations? |
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Definition
| Insertions and deletions. |
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|
Term
| What is a point mutation? |
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Definition
| 1 single individual base error |
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Term
| What causes an inversion? |
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Definition
| Damage causes a double stranded break in DNA. Repair mechanism fixes the break but flips the broken segment. |
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Term
| What causes a transposition? |
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Definition
| When a double stranded break happens on 2 different chromosomes, the two end can get switched by the repair mechanism. |
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Term
| If you inserted 2 bases into a gene sequence, in what reading frame would you be downstream of the insertion? |
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Definition
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Term
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Definition
| Two of the same protein together. |
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Term
| What does MutS look for as it moves along the DNA? |
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Definition
| Bump outs caused by mismatches. |
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Term
| Which direction does MutS move along DNA? |
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Definition
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|
Term
| Which protein recruits MutL? |
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Definition
|
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Term
| What is the function of MutL? |
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Definition
| It is an endonuclease. It nicks one strand of DNA near the mismatch allowing for exonuclease activity. |
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Term
| [image]What species is this? |
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Definition
| E. coil because of the presence of MutH. |
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Term
| After incision by MutL (or homologues or MutH in E. coli) what proteins remove the error-containing strand? |
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Definition
| Helicases and exonucleases. |
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Term
| What protein fills the gaps in DNA mismatch repair? |
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Definition
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Term
| What protein seals nicks in DNA? |
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Definition
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