Download Teacher Kit Transcription

Protein Synthesis Teacher Manual
Thank you for the purchase of the Protein Synthesis Manipulative Kit. This
kit was designed and developed for use in the science classroom by a science
teacher. All of us are aware that abstract concepts can be difficult for our
students. I’m confident that this product can make it easier for you to teach,
and for your students to learn protein synthesis.
In this manual, I will give you some ideas on how to get started using your
new kit. The included CD will also be useful for this purpose. I'm sure, that
in time you will discover a host of new applications and situations in which
it can be used.
Placement of Magnets
Locate the box of magnets in your kit. Attach them to the back of your
manipulatives according to Appendix D. Clean and dry the surface of the
magnet and application site before application of glue. Epoxy, hot glue or a
good plastic glue will work.
Teacher Kit
Transcription
The Teacher Demonstration Kit begins with a double stranded DNA
Model. Consisting of:
• A 3'-5' DNA strand (sense strand)
• A linear 5'-3' DNA strand (anti-sense) and
• DNA in the double helix that your students are probably most familiar
with. The helix is included to prevent the misconception that the entire
strand of DNA uncoils and is transcribed.
1. Arrange these three manipulatives on the board
2. Point out the features of the model.
 Backbone (phosphates-Yellow) (DeoxyRibose sugar-Black)
 Nucleotide bases
 Area of hydrogen bonding
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3. Introduce the RNA polymerase enzyme manipulative. Use the enzyme to
simulate the breaking of the hydrogen bonds between the DNA
nucleotides as you physically separate the two complementary DNA
strands.
4. Ask students to identify the RNA nucleotides complementary to each of
the bases on the now single stranded 3'-5' DNA “sense strand”.
5. Bond the requested RNA nucleotides to their complementary DNA
nucleotides.
 You have enough RNA nucleotides to build a complete mRNA
6. Introduce the complete mRNA manipulative. This comes in two pieces
which are hinged together to allow for shipping.
7. Compare this mRNA to the one you just produced in (step 5). Verify for
students that the RNA base sequence is the same in both.
8. Remove the individual RNA nucleotides from the board and bring back
together the two complementary DNA strands.
9. Move the mRNA out of the nucleus through a nuclear pore and into the
cytoplasm. Use tape or draw a line on your board to represent the
nuclear membrane. A gap in the line will represent the opening of the
nuclear pore.
 Let students know that what has just taken place is transcription. The
“blueprint” encoded in DNA has been transcribed into the message of
mRNA. Stress that the entire process takes place in the nucleus of
eukaryotes.
 When teaching advanced students this is a good time to discuss mRNA
processing with subsequent splicing of introns and exons.
 This is also a good time to bring out an overhead or model of a eukaryote
cell in cross section. Point out the nuclear membrane, nuclear pore,
rough entoplasmic reticulum and the ribosomes. This will give students a
visual picture of where cellular protein synthesis events are taking place.
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Teacher Kit
Translation
10. Now point out the features of the mRNA manipulative.
 Point out the change in color of the sugar in the “backbone” to indicate
the change from deoxyribose to ribose sugar.
 Point out the codons, artificially grouped in three’s for emphasis.
11. Attach the ribosome manipulative to the board.
• Inquire what the ribosome is made of: Ans: RNA-protein complex and
• consists of a large and small subunit.
•
Inquire about the two sites that will be occupied by t-RNA: The “P”site
(on the left) and “A” site (on the right).
• How deep you want to go into the origin and structure of ribosomes will
depend on the level of your students.
12. Simulate the mRNA initiator codon (A-U-G) entering the “P” site of the
ribosome with the second codon (A-U-C) occupying the “A” site.
 Now that you have the initiator codon in the “P” site of the ribosome,
inquire what the anti-codon complementary to the codon on the mRNA
would be.
13. Place the transfer RNA with the (U-A-C) anti-codon on the board.
 Now is a good time to discuss structure and function of tRNA, codons
and anti-codons.
 Provide students with a copy of the Genetic Code Table included in
Appendix A at the end of this manual. This table provides the amino
acids specified by each codon sequence on mRNA . Ask them to specify
the amino acid that should be attached to this (U-A-C) tRNA
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14. Attach the Methionine (MET) amino acid to the first t-RNA
15. Move the Methionine tRNA to the “P ” site on the ribosome. Line up
the complementary anti-codon with the codon on the mRNA.
 Inquire what the tRNA anti-codon complementary to the mRNA codon
now occupying the “A” site on the ribosome would be?
16. Place the tRNA with the ( U-A-G) anti-codon on the board
 Using their table (Appendix A) have students identify the amino acid to
be attached to this t-RNA
17. Attach the Isoleucine (Ile) amino acid to the second t-RNA
18. Move the Isoleucine tRNA to the “A” site on the ribosome. Line up the
complementary anti-codon with the codon on the mRNA.
19. Insert the peptide bond manipulative between the Methionine and
Isoleucine amino acids
 Depending on the level of students you are instructing, this may be a
good time to teach peptide bonding between amino acids.
20. Shift the ribosome one reading frame to the right so the Isoleucine codon
is now in the “P” site of the ribosome.
21. Move the Methionine t-RNA to the bottom of the board to simulate
return to the cytoplasm for the purpose of obtaining another amino acid.
 Ask students what the anti-codon complementary to the codon (C-A-G)
now in the “A” site on the mRNA would be?
22. Place the tRNA with the (G-U-C) anti-codon on the board
 Using their table (Appendix A) have students identify the amino acid to
be attached to this t-RNA.
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23. Attach the Glutamine (Gln) amino acid to the third t-RNA
24. Move the Glutamine tRNA to the “A ” site on the ribosome. Line up the
complementary anti-codon with the codon on the mRNA.
25. Insert the model representing the peptide bond between the Isloleucine
and Glutamine amino acids.
26. Shift the ribosome one frame to the right so the Glutamine is now in the
“P” site.
27. Move the isoleucine t-RNA back into the cytoplasm.
 Ask students what the anti-codon complementary to the codon (G-U-A)
now in the “A” site on the ribosome would be?
28. Place the tRNA with the (C-A-U) anti-codon on the board.
 Using their table (Appendix A) have students identify the amino acid to
be attached to this t-RNA
29. Attach the Valine (Val) amino acid to the last t-RNA
30. Move the Valine tRNA to the “A ” site on the ribosome. Line up the
complementary anti-codon with the codon on the mRNA.
31. Insert the model representing the peptide bond between the Glutamine
and Valine amino acids.
32. Move the Glutamine t-RNA back into the cytoplasm.
33. Shift the ribosome one frame to the right so the Valine is now in the “P”
site and the stop or termination codon is in the “A” site. This codon
signals release of the ribosome and release of the newly formed
polypeptide.
 Check student understanding. Call for student volunteers to explain the
process using the manipulatives. Use good questioning techniques to
check for misconceptions.
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Student Kit
The student kit is designed to provide students the opportunity to practice
the concepts introduced with the teacher demonstration manipulatives. It is
also designed to allow the teacher an opportunity to assess student learning
in an efficient manner. You will quickly discover individual student
misunderstandings and be able to pinpoint where remedial help is required.
NOTE: Be sure that you provide erasable markers for students to write
codes on the student manipulatives. If proper markers are used the
manipulatives can be erased and should last indefinitely. If replacement
parts are required contact United Scientific.
The student set consists of:

DNA “sense strands” with pre-printed DNA base sequences. There are
four different sequences. Each sequence is labeled 1-4 at the top of each
strand. There are five copies of each of the four sequences for a total of
twenty strands. Each of the four pre-printed DNA base sequences will
produce a unique 5 amino acid sequence. The correct amino acid
sequence for each of the four pre-printed DNA base sequences can be
found in Appendix B of this manual. Use this key to quickly check the
final step of a student’s work. If the students amino acid sequence does
not match your key, check that the student has written the correct codons
and anti-codons.

Blank DNA strands upon which students code the bases complementary
to the bases on the above “sense strand”

Blank messenger RNA strands upon which the student writes the codons
derived from the DNA “sense strand”

Blank transfer RNA’s upon which the student writes the anti-codons
complementary to the mRNA codons
 Blank polypeptide chain upon which the student codes the amino acid
sequence. If correct this code will correspond to the teacher key in
Appendix B. The three letter abbreviations for the amino acids can be
found in Appendix C and should be copied for student use.
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Procedure:
1. Provide each student or group, one of each of the manipulatives listed
above and an erasable marker.
2. Explain to students what each of the manipulatives represents.
3. Direct students to code WITH ERASABLE MARKER:

the DNA bases complementary to the pre-printed bases on the blank
DNA strand
 the mRNA codons complementary to the pre-printed DNA “sense strand”
bases on the blank mRNA.

the tRNA anti-codons complementary to the mRNA codons on the blank
transfer RNA’s

the three letter abbreviations (found in Appendix C) for the resulting
amino acid sequence.
Use the key in Appendix B to check student work. The correct amino acid
sequence for each of the four pre-printed DNA base sequences can be found
in Appendix B of this manual. Use this key to quickly check the final step
of a student’s work. If the students amino acid sequence does not match
your key, check that the student has written the correct codons and anticodons.
You will be amazed at how quickly your students learn protein synthesis.
Take good care of your kit and it will provide you years of service.
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APPENDIX A
GENETIC CODE IN RNA FORMAT
2nd base in codon
C
A
G
C
A
G
Phe
Phe
Leu
Leu
Leu
Leu
Leu
Leu
Ile
Ile
Ile
Met
Val
Val
Val
Val
Ser
Ser
Ser
Ser
Pro
Pro
Pro
Pro
Thr
Thr
Thr
Thr
Ala
Ala
Ala
Ala
Tyr
Tyr
STOP
STOP
His
His
Gln
Gln
Asn
Asn
Lys
Lys
Asp
Asp
Glu
Glu
Cys
Cys
STOP
Trp
Arg
Arg
Arg
Arg
Ser
Ser
Arg
Arg
Gly
Gly
Gly
Gly
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U
C
A
G
U
C
A
G
U
C
A
G
U
C
A
G
3rd base in codon
1st base in codon
U
U
APPENDIX B
TEACHER KEY TO STUDENT WORK
#1
Pre- Printed DNA Sequence
C-G-T-A-A-T-C-T-C-A-T-A-G-C-T
Codons
GCA---UUA---GAG---UAU---CGA
Anti-Codons
CGU---AAU---CUC---AUA---GCU
Amino Acids
Ala-----Leu----Glu------Tyr------Arg
#2
Pre-Printed DNA Sequence
A-A-A-G-G-A-T-A-T-C-A-C-C-C-A
Codons
UUU---CCU---AUA---GUG---GGU
Anti-Codons
AAA---GGA---UAU---CAC---CCA
Amino Acids
Phe-----Pro------Ile------Val-----Gly
#3
Pre-Printed DNA Sequence
T-A-G-C-G-C-C-T-G-G-T-C-T-T-T
Codons
AUC---GCG---GAC---CAG---AAA
Anti-Codons
UAG---CGC---CUG---GUC---UUU
Amino Acids
Ile------Ala-----Asp-----Gln----Lys
#4
Pre-Printed DNA Sequence
A-C-C-G-C-G-C-T-C-G-A-C-T-T-C
Codons
UGG---CGC---GAG---CUG---AAG
Anti-Codons
ACC---GCG---CUC---GAC---UUC
Amino Acids
Trp----Arg------Glu------Leu----Lys
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APPENDIX C
Three Letter Abbreviations for the 20 Amino
Acids
Ala: Alanine
Cys: Cysteine Asp: Aspartic acid Glu: Glutamic acid
Phe: Phenylalanine Gly: Glycine
His: Histidine Ile: Isoleucine
Lys: lysine Leu: Leucine Met: Methionine Asn: Asparagine
Pro: Proline Gln: Glutamine Arg: Arginine Ser: Serine
Thr: Threonine Val: Valine Trp: Tryptophane Tyr: Tyrosisne
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Appendix D
Suggested Placement of Magnets
11
Total 1” Magnets in Kit = 45
Glue to back of manipulatives using a strong adhesive designed for use with plastic
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surfaces.
Protein Synthesis Manipulative Item #:PSYKIT
Parts list
Teacher Manipulatives
PART Description
DNA Double Helix
DNA 5'-3' Strand
DNA 3'-5' Strand
A-RNA Nucleotide
C-RNA Nucleotide
G-RNA Nucleotide
U-RNA Nucleotide
mRNA Left (AUG-AUC)
mRNA Right(CAG-GUA-UAG)
Ribosome
tRNA (anticodon UAC)
tRNA (anticodon UAG)
tRNA (anticodon GUC)
tRNA (anticodon CAU)
Amino Acid (Met)
Amino Acid (Gln)
Amino Acid (Ileu)
Amino Acid (Val)
Peptide Bonds (Black Bars)
RNA Polymerase Enzyme
PART No.
T-1
T-2
T-3
T-4
T-5
T-6
T-7
T-8L
T-8R
T-9
T10
T11
T12
T13
T14
T15
T16
T17
T18
T19
Qty./Set
1
1
1
5
2
4
4
1
1
1
1
1
1
1
1
1
1
1
3
1
Student Manipulatives
DNA 5'-3' #1
DNA 5'-3' #2
DNA 5'-3' #3
DNA 5'-3' #4
DNA 3'-5' (blank,pink)
mRNA (blank, green)
tRNA (blank, lt.blue)
Amino Acid Chain (1-5 yellow)
S1
S2
S3
S4
S5
S6
S7
S8
Replacement Parts can be ordered from your kit supplier.
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5
5
5
5
20
20
100
20