Download BIOLOGY-DNA replication, transcription, translation (DOC 98KB)

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P A S S
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DNA Replication, Transcription & Translation
Questions for each group to discuss and report back to the group OR briefly discuss as a
whole class before starting the activity.
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Why does DNA replicate?
Does each new cell need DNA to be present?
Where does the extra DNA come from?
Does DNA replication end when the old DNA creates a completely new DNA?
What is the type of replication that DNA goes through called and what does this
mean?
Where does translation take place?
In which direction is DNA built or constructed, and why?
What type of bond exists between nitrogenous bases?
Are these strong or weak bonds?
Building DNA double helix
Materials: Pipe-Cleaners, Pegs (5 colours).
Pipe-Cleaners will represent the phosphorous/ sugar back bone. The PASS facilitators will
need to demonstrate this, perhaps on the board. Various colours of pegs will be used to
represent the bases C, A, G and T. Students will need to explain where the sugar is joined
to the nitrogenous base and the type of bonds found between them.
Give the students the following code sequence to build a model:
5’ ATGTTTAAGGTGGAGCCC 3’
Replication, Transcription & Translation
Using their original DNA strand made from pipe-cleaners and pegs, the students are to
play out:
 Replication of the code
 Transcription from the template
 Translation to the Amino Acid sequence
Here we need to give them the 5th colour pegs representing Uracil. Students will need to
remember at which point they must use Uracil rather than Thymine.
Give this to the students:
5’ ATGTTTAAGGTGGAGCCC 3’
- DNA Code
Get the students to produce this:
3’ TACAAATTCCACCTCGGG 5’
-DNA template
Check that the students can transcribe the correct mRNA sequence from the DNA
template:
5’ AUGUUUAAGGUGGAGCCC 3’
-mRNA
Check that the students can translate (using the Codon table) to the correct Amino
Acid sequence:
Met –Phe –Lys –Val –Glu - Pro
-Amino Acid sequence
Questions for Students:
 What is a start codon?
 Does all mRNA use the sequence AUG for the start codon?
Second Position of Codon
U
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C
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(5’)
G
U
C
A
G
UUU Phe
UUC Phe
UUA Leu
UUG Leu
UCU Ser
UCC Ser
UCA Ser
UCG Ser
UAU Tyr
UAC Tyr
UAA Ter
UAG Ter
UGU Cys
UGC Cys
UGA Ter
UGG Trp
U
C
A
G
CUU Leu
CUC Leu
CUA Leu
CUG Leu
CCU Pro
CCC Pro
CCA Pro
CCG Pro
CAU His
CAC His
CAA Gln
CAG Gln
CGU Arg
CGC Arg
CGA Arg
CGG Arg
U
C
A
G
AUU Ile
AUC Ile
AUA Ile
AUG Met
ACU Thr
ACC Thr
ACA Thr
ACG Thr
AAU Asn
AAC Asn
AAA Lys
AAG Lys
AGU Ser
AGC Ser
AGA Arg
AGG Arg
U
C
A
G
GUU Val
GUC Val
GUA Val
GUG Val
GCU Ala
GCC Ala
GCA Ala
GCG Ala
GAU Asp
GAC Asp
GAA Glu
GAG Glu
GGU Gly
GGC Gly
GGA Gly
GGG Gly
U
C
A
G
T
h
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d
P
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n
(3’)