DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA...
Transcript of DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA...
![Page 1: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/1.jpg)
DNA
REPLICATION and
MUTATIONS
![Page 2: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/2.jpg)
DNA Replication
Replication – the process of copying a
DNA molecule.
So that genetic information can be passed on
from cell to cell.
DNA replicates before cells divide (S
phase)
![Page 3: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/3.jpg)
DNA is made up of 2 strands of nucleotides.
The strands are held together by HYDROGEN BONDS between each of the bases.
The 2 strands are
COMPLEMENTARY
A pairs with T
C pairs with G
Quick Review…
![Page 4: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/4.jpg)
How it Works
During replication EACH strand is used as
a pattern (template) to make 2 new DNA
molecules
This is called semi-conservative
replication
![Page 5: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/5.jpg)
Original DNAOriginal LEFT with
new right strand
Original RIGHT with
new left strand
AND
How it Works
![Page 6: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/6.jpg)
Steps in DNA Replication
1. Double helix unwinds.
2. DNA helicase (an ENZYME) ―unzips‖
the DNA molecule, breaking the
hydrogen bonds between the strands
DNA helicase
(enzyme)
Unpaired
bases
![Page 7: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/7.jpg)
Steps in DNA Replication
3. DNA Polymerase (another ENZYME)
pairs up free nucleotides in the nucleus
with the nucleotides on the DNA strands
forming new hydrogen bonds.
Where do nucleotides come from? YOU ARE WHAT YOU EAT!
![Page 8: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/8.jpg)
DNA
unzips
Original
DNAFree nucleotides
pair up with the
original LEFT
strand
Free nucleotides
pair up with the
original RIGHT
strand
Steps in DNA Replication
![Page 9: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/9.jpg)
Steps in DNA Replication
4. The DNA winds back up into a double helix.
The final products of DNA replication are two molecules of DNA each having half new material and half old material… ―Semi-conservative‖
![Page 10: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/10.jpg)
DNA Replication
Growth
Growth
Replication
fork
DNA
polymerase
Original
strand DNA polymerase
Nitrogenous
bases
Replication
fork
Original strandNew strand
New strand
![Page 11: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/11.jpg)
Now all genetic information can be
passed onto new cells during cell
division.
DNA
copied
2 new identical cells
Why Replicate?
![Page 12: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/12.jpg)
Polymerase Chain Reaction
(PCR)
Can be used to make millions of copies of
a DNA sequence from a very small sample
Forensics, paternity testing, etc.
PCR Video
![Page 13: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/13.jpg)
Accuracy
Replication is also very accurate – only
ONE IN A BILLION base pairs are
incorrectly paired.
When mistakes are made, the DNA
molecule can correct itself so the genetic
code remains the same.
Sometimes they can’t… MUTATIONS
![Page 14: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/14.jpg)
GENE MUTATIONS
(in DNA)
![Page 15: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/15.jpg)
Point Mutations Happen At
Single Nucleotide Points in DNA
SubstitutionOne base changes to (―subs‖
for) another
Insertion Base added (inserted)
Deletion Base removed (deleted)
![Page 16: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/16.jpg)
The Dog Ate The Fat Cat
Substitution
The Dog Ate The Fat Rat
Deletion
The Oga Tet Hef Atr At..
Insertion
The Dog Tat Eth Efa Tra t
![Page 17: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/17.jpg)
What kind of point mutation?
![Page 18: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/18.jpg)
What kinds of point mutation?
![Page 19: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/19.jpg)
Insertions and Deletions Can Cause
FRAMESHIFTS in the code!
Uh Oh! One nucleotide affected every
codon down the line—a frameshift!
![Page 20: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/20.jpg)
Now:
CHROMOSOMAL MUTATIONS
(affect whole chromosomes)
![Page 21: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/21.jpg)
What Would You Call It?
Deletion
![Page 22: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/22.jpg)
What Would You Call It?
normal chromosome
one segment repeated
three repeats
DuplicationOne or more segment is repeated
![Page 23: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/23.jpg)
InversionA linear stretch of DNA is reversed within the
chromosome
What Would You Call It?
![Page 24: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/24.jpg)
TranslocationEntire gene segments are exchanged between non-homologous
chromosomes!
chromosome
nonhomologou
s chromosome
reciprocal
translocation
![Page 25: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/25.jpg)
Check Point
![Page 26: DNA REPLICATION and MUTATIONS...DNA Replication Replication –the process of copying a DNA molecule. So that genetic information can be passed on from cell to cell. DNA replicates](https://reader030.fdocuments.us/reader030/viewer/2022040512/5e5fb6059c04684dd469e1ab/html5/thumbnails/26.jpg)
Mutations may be:
Silent or neutral (no effect)
Harmful or Fatal (bad effect)
Beneficial (good effect, low probability)