Download Simulating Protein Synthesis

Name________________________________________
Simulating Protein Synthesis
Mr. and Mrs. Potato Head
Mr. and Mrs. Potato Head have been married for many years. Now that the couple is
expecting their first child, they are coming to you for your help. Playschool Doctors
Clinic has just hired you as a Potato Head Genetic Code Reader and Translator. The
clinicians in the lab have been able to extract the DNA of Mr. and Mrs. Potato Heads
new spud. They have also removed the introns for you. Now it is your job to show them
what their small fry will look like.
A review of DNA transcription and translation….
o Transcription takes place in the nucleus of the cell. mRNA is a copy of a
segment of DNA.
o The mRNA carries this information in the form of a code to the ribosome, where
protein synthesis takes place. The code specifies the order of amino acids,
which are joined to form a polypeptide.
o mRNA is not directly recognized by the corresponding amino acids. tRNA is
needed to bring the mRNA and amino acids together.
o As the code carried by the mRNA is “read” on the ribosome, the proper tRNAs
arrive, carrying the proper amino acids. This will “grow” the polypeptide chain.
o Translation is the process which DNA is transferred to the language of proteins.
Confused? Look in your book, ask your partner then ask your teacher.
You will simulate the mechanism of protein synthesis and therefore determine the traits
of the new baby spud. Potato Heads are made up of several genes (A, B, C, D, E, F, G,
H, I, and J).
Materials: baby spud (1 per pair) and pencils.
Procedure
1. To determine the trait for your baby spud, fill in the information in the box labeled
Gene A in the data table. Notice the sequence of nucleotides in DNA. On the
line provided, write the sequence of the nucleotides for the mRNA that is
complimentary to DNA (transcription).
2. In order to determine the sequence of amino acids, match each mRNA codon
with the specific amino acid number in figure 1. Using a – (hyphen) to separate
each amino acid number, record this information in the appropriate place in the
Data Table. (ex: 2-6)
3. Using figure 2, find the trait that matches the amino acid sequence. Record this
information in the appropriate place in Gene A Data Table.
(Ex: 2-6 = both pierced ears)
4. Repeat steps 1-3 for the remaining genes.
5. When your data table is complete, build your new baby spud!
6. CHECK YOUR WORK: Compare the spud you build with the corresponding
photo. (Teacher will give location of photos)
Name________________________________________
Post Lab Questions:
List at least 3 differences between transcription and translation? (3)
Transcription
1
2
3
Translation
1
2
3
What is a gene? (1)
Using the genetic code, identify the amino acids that have the following messenger
RNA strand codes (Hint: use the codon to amino acid chart)
UGG-CAG-UGC-CGU (2)
____________________________
“The making of the various types of protein is one of the most important events for a cell
because protein not only forms structural components of the cell; it also composes the
enzymes that catalyze the production of the remaining organic biomolecules necessary
for life.”
Using Wikipedia as a source, list 3 proteins made in the human body and its function. (3)
1.________________:
2.________________:
3.________________:
Baby Spud was accidentally mistaken for a baked potato and thrown in the microwave.
Fortunately she was saved, but not before damage was done to her DNA sequence.
Originally her DNA was GGA-CTC-AAA and now is GGA-CTC-TTT. Explain how this
unfortunate has changed her gene expression. (1)