Genetics Quiz 1 Genetic Flow

Front 1

The cell must preserve the integrity of genetic information, so DNA replication must be very accurate

Back 1

Fidelity

Front 2

Does a DNA pol or RNA pol require a primer?

Back 2

DNA pol only!

Front 3

Does DNA replication require a template?

Back 3

Yes!

Front 4

Which organism can have multiple origins of replication?

Back 4

Eukaryotics

Front 5

Pre-priming Stage

Back 5

1. DNA A-recognizes OriC
2. DNA B (helicase), DNA C (loading) continue unwinding
3. SSB-prevent re-annealing

Front 6

What stage of DNA replication is the regulating stage, in which if this process starts, replication will be carried out completely?

Back 6

Pre-priming Stage

Front 7

Priming/Initiation Stage

Back 7

1. Primase makes RNA primer (does not need 3'OH, no proofreading)
2. DNA Pol catalyzes attachment of nucleotides
3. Primosomes: accessory proteins

Front 8

Elongation for leading strand

Back 8

1. DNA pol III:
a. 5' to 3' Pol
b. 3' to 5' Exonuclease (proofreading)

Front 9

What separates parents strands?

Back 9

Helicase

Front 10

What prevents re-annealing of parent strands?

Back 10

SSB: single-stranded DNA binding protein

Front 11

What unwinds in front of the fork, negative unwounding to relieve stress

Back 11

Gyrase

Front 12

The drug ciprofloxicin inhibits what?

Back 12

Gyrase so DNA replication stops

Front 13

Elongation-lagging strand

Back 13

DNA pol I:
1. 5'-->3' DNA synthesis "pol"
2. 3'-->5' exonuclease "proofreading"
3. 5'-->3' exonuclease removes RNA primer

Front 14

What is the difference between DNA Pol I and III?

Back 14

DNA Pol I has 5' to 3' exonuclease that removes RNA primer

Front 15

Segregation

Back 15

linked circles are separated using topoisomerase

Front 16

The next replication cycle begins before the one ahead of it finishes.

Back 16

True for Prokaryotes but not for eukaryotes (only one replication at a time)

Front 17

Priming/Initiating Enzyme in eukaryotes

Back 17

1. DNA pol alpha: initiates DNA synthesis, primase activity, no proofreading, can put in short segments of DNA
2. DNA pol delta: major elongating enzyme, proofreading
3. 6-7 additional DNA pol.

Front 18

Where are telomers added?

Back 18

To the extreme 3' end of the template for the lagging strand

Front 19

Telomerase contains?

Back 19

1. Portable RNA
2. Reverse Transcriptase

Front 20

G1
gap stage or growth stage

Back 20

Lots of metabolism, run-of-the-mill activities

At end, "checks" if OK to replicate/divide
time variable

2n DNA

Front 21

S

Back 21

DNA synthesis
6-8hrs

4n DNA

Front 22

G2
gap stage

Back 22

Prepare for cell division
2-5 hrs.

4n

Front 23

M

Back 23

-Mitosis
-1hr.
-Chromosomes condense, migrate to opposite sides, cell divides into 2 daughter cells
-4n becomes 2n and 2n

Front 24

Go

Back 24

-indefinite duration
-for non-dividing cells
-for most cells in body
-cell still undergoes metabolic activity but never divides
-2n

Front 25

Regulation of DNA replication

Back 25

At G1, G2, and M

Front 26

G1 Start
Questions to ask

Back 26

1. Environmental conditions good for replication?
2. DNA in good shape?

Front 27

G2 checkpoint
Questions to ask

Back 27

1. Is replication complete?
2. Cell ready to divide?

Front 28

M checkpoint
Questions to ask

Back 28

At end of M (at metaphase)
1. Are all chromosomes condensed?