Download Pogil activity DNA to protein

NAME: ____________________________________ DATE: ___________ BLOCK: _____
Work as a group as you complete this activity. You should work together to complete
the two diagrams and to answer the questions. Be sure that everyone in your group is
playing an active role in successfully completing this activity!
In the last unit, you learned about the structure of DNA. You also learned what a gene is (a
section of DNA) and what a gene makes (a protein). This activity is designed to help you
figure out HOW a gene makes a protein.
In Figure 1 below, there is a section of DNA that codes for a protein (a gene). This gene would
be in the nucleus of a cell along with many thousands of other genes arranged on
chromosomes. This gene is much smaller than genes are in real life, but it will give you the
idea of how this process works. During a process called transcription, DNA in the nucleus is
used to make a molecule called mRNA (messenger RNA). This works with a base pair
system similar to what you learned when DNA makes a copy of itself with a key difference.
Your groups should try to figure out the base pairing system between DNA and mRNA using
the first two codons (segments of three bases) and fill in the blank boxes with the appropriate
letters. After you have completed the mRNA sequence, have your teacher check your work
BEFORE you answer the questions.
Type Response Here (text in cells is set to white for spacing)
AUG
Content
CUA
AAA
AAA
AAA
AAA
AAA
Questions:
1. How is mRNA different than DNA?
2. How is mRNA the same as DNA?
3. What process uses DNA to make mRNA?
4. Where in a cell do you think this process of DNA making mRNA occurs?
HEY, READ THE SET OF INSTRUCTIONS BELOW!!!!!!!!!!
*Copy the letters from the mRNA on the previous page to the boxes below for Figure 2’s mRNA.*
Messenger RNA is like a middle man. DNA makes mRNA during TRASNCRIPTION, some
pieces of mRNA get edited out during a step called mRNA PROCESSING, and final mRNA
molecule leaves the nucleus, enters the cytoplasm and is used to make a protein during a step
called TRANSLATION. Remember, the end goal of a gene is to make a protein, but it uses a
middle man molecule to do so. In Figure 2 you will see how mRNA is used to code for a
protein which is put together with the help of a ribosome. In your group, try to figure out how to
use the codon chart file on my wiki to decode the message of mRNA. A codon is three bases
in a row that code for a specific amino acid. For example, CAG codes for glutamine.
Complete the rest of the protein (amino acid sequence) using the codon chart. The amino
acids are abbreviated using the first 3 letters of the name – for example methionine is labeled
met. After you have completed the protein, have your teacher check your work BEFORE you
answer the questions.
Type Response Here (text in cells is set to white for spacing)
AUG
CUA
AAA
AAA
AAA
AAA
AAA
met
leu
AAA
AAA
AAA
AAA
AAA
Content Questions
5. What is the process called that uses mRNA to make a protein?
6. What cell structure makes protein?
7. What is the chemical bond between two amino acids called?
8. What amino acid is coded for by the codon ACC? Use the codon chart for this one!
9. Why do you think the stop codon is at the end of the mRNA molecule?
Application Questions
10. If you had the following amino acids bonded together, what would the mRNA look like that
makes this very small protein? met---lys---val---leu---tyr
11. For the above question, will the mRNA always be exactly the same? Why or why not?
12. In some genetic disorders, a mutation occurs. A mutation means the sequence of the
DNA bases changes. Look back at the DNA sequence on page 1. Change the first G in
the DNA to an A (This is called a POINT MUTATION)? What happens to the mRNA at that
spot? What happens to the amino acid at that spot? Does this change any of the other
amino acids?
13. During mRNA Processing in eukaryotes, mRNA is altered by pieces getting cut out.
Pieces that are cut out are called introns. The pieces that remain are called exons and
get spliced together and are used for translation by a ribosome. What would the amino
acid sequence be for Figure 2 if CUA was an intron?
14. Explain how one gene differs from another gene.
15. A small protein in your body has 100 amino acids joined together. How many codons
would the DNA have that makes this protein?
16. Explain how a gene might have 201 codons, but only 184 amino acids in the protein.
17. If a gene has 900 bases, how many codons does it have?
18. If that same gene (900 bases) has 300 bases that are introns, how many amino acids
would be in the protein?
GREAT WORK!!!!!!!!