Transcript Decode the following message.

Decode the following message.
CGCGGCCATGTC
Codon
Codes for
AAA
AUC
CAG/ CAC
CCG
a cat
ate
brown
dog
GUA
GCG
UGG
is
my
old
UGA
STOP
Decode the following message.
CGCGGCCATGTC
Change your code based on your assigned
group and decode again.
GROUP 1- Change the last C to a G.
GROUP 2- Remove the last 3 bases. Replace
them with TTT.
GROUP 3- Move the A between the two Cs.
GROUP 4- Remove the last 3 bases. Replace
with ACC.
GROUP 5- Remove the last 6 bases. Replace
with TAG TTT.
Codon
Codes for
AAA
AUC
CAG/ CAC
CCG
a cat
ate
brown
dog
GUA
GCG
UGG
is
my
old
UGA
STOP
Make observations about the change
that has occurred from the normal
strand to the one below it.
Make observations about the change
that has occurred from the normal
strand to the one below it.
Make observations about the change
that has occurred from the normal
strand to the one below it.
Gene Mutations: Substitution
• Substitution= one nucleotide base pair
substituted for another in a DNA sequence at
single point (point mutation)
• A change in one base pair = possible change in
one amino acid sequence
GATTTA
CUAAAU
GAATTA
CUUAAU
GCTTTA
CGAAAU
Leu Asn
Leu Asn
Arg Asn
(no change/silent
mutation)
(1 amino acid
changed)
Gene Mutations: Insertion
(Frameshift Mutation)
• Insertion- one or more nucleotide base pairs
added into a DNA sequence at a single point.
• An insertion of one base pair causes a shift in
the reading frame = One or more amino acids
Base Pair
changed
Inserted
CACTTTGGT CACATTTGGT
GUGAAACCA GUGUAAACCA
Valine Lysine Proline
Valine STOP
Gene Mutations:Deletion
(Frameshift Mutations)
• Deletion - one or more nucleotide base pairs
removed from a DNA sequence at single point.
• An deletion of one base pair causes a shift in
the reading frame = One or more amino acids
changed
Base Pair
Removed
CACTTTGGT
GUGAAACCA
Val Lys Pro
CCTTTGGT
GGAAACCA
Gly Thr
Mutations & Location
• Mutations in an unexpressed area of the
chromosome will have no effect on the
phenotype of an individual.
• If mutations occur within the gametes, they
can be inherited and expressed in the
phenotype of an individual
What happens when errors occur?
• An error occurs in transcription in 1 out of
100,000 base pairs transcribed.
• When this occurs, an RNA polymerase known
as pol II "backtracks," or reverses, along the
transcript to remove the damaged
nucleotides.
Gene vs. Chromosomal Mutations
Gene Mutations
Chromosomal Mutations
Scale
Small-Scale
Large -Scale
Types
Substitution, Insertion, Deletion
Duplication, Deletion,
Translocation, Inversion,
Nondisjunction
Quickwrite
Would it be worse for an error to
occur during DNA replication or
transcription? Why?