Name ________________________________________
Assignment #____
RNA and Protein Synthesis Lab
Background:
Genes are coded DNA instructions that control the production of proteins within the cell. The first step in
decoding these genetic messages is to copy part of the nucleotide sequence from DNA into messenger
RNA (mRNA). This step is called Transcription. It then leaves the nucleus and travels to out into the
cytoplasm of the cell, where it attaches to a ribosome. The mRNA is then “read” by the ribosome. This
process is called Translation. After the mRNA attaches to the ribosome, transfer RNA (tRNA) molecules
line up along the mRNA molecule based on the complementary pairing of tRNA anticodons to the mRNA
codons. The amino acids that the tRNA molecules are carrying are joined together by peptide bonds,
creating a long chain before the process is complete. Long chains of amino acids form polypeptides, a.k.a.
proteins.
In today’s activity, you will be completing the process of transcription and translation to create a 6 unit
polypeptide chain (protein).
Procedure:
1. Copy the DNA sequence you were given onto line #1 of your data sheet
2. Transcribe that DNA template strand into the complementary mRNA strand
3. Reading the mRNA strand in codons (groups of 3 bases [letters] at a time); you will use your
amino acid “decoder” wheel to determine the correct amino acid sequence for your protein. (you
may abbreviate the amino acids by using the first 3 letters of each amino acid’s name) (ex:
isoleucine = iso)
a. You must first follow the sequence until you find the “start” codon. Once you find the
“start” codon, you will begin with it to sequence the amino acids to create your protein.
b. Continue sequencing the amino acids for your protein until you reach one of three possible
“stop” codons.
4. After you have determined the correct sequence for your amino acids, you can begin to “construct”
your protein chain. There is a basket of “amino acids” under the hood in the back of the room.
Find the ones you need and take them back to your desk so you and your team may construct your
chain.
5. Once you have completed constructing your protein, look at the chart and determine what kind of
protein you created.
6. Research your protein and write a summary of what its function is.
Data:
1. DNA template strand:
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2. Complementary mRNA strand:
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3. Amino Acid Sequence:
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4. Name of protein constructed:
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5. Function of protein constructed:
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Analysis:
1. List the two main steps in protein synthesis. 1. ________________________________________
2. ________________________________________
2. What are the building blocks of proteins? _____________________________________________
3. Where does step one of protein synthesis occur? ________________________________________
4. Where does step two of protein synthesis occur? ________________________________________
5. What amino acid does every protein begin with? ________________________________________
6. What could/would happen to your constructed protein if you copied the original DNA template
strand incorrectly? ________________________________________________________________
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