notes

1. Translation:
mRNA to protein

2. How is DNA used to make proteins?
DNA  mRNA  Protein
Transcription Translation
DNA mRNA Protein

3. Processing Piece:
1) What are the building blocks of proteins?
2) A polypeptide chain is a chain of ______________.

4. What is translation?
When mRNA is used to make protein.
Where does translation happen?
At the ribosome

5. Processing Piece:
• Draw a picture to help yourself remember the
definition of translation.
(Example: A waitress takes the order to the
kitchen where it is used to make the food.)

6. What is a codon?
• 3 bases (“letters”) of a DNA or mRNA sequence.
Example: CAG
• Each codon is the instructions for one amino acid.
What is an anticodon?
• 3 bases (“letters”) that will pair up with a codon.
• Found on tRNA

7. Processing Piece:
2) If the bases on a codon are UGC, what will the
bases on the anticodon be?
3) If the bases on a codon are GCU, what will the
bases on the anticodon be?

8. What is tRNA?
• A small, folded piece of RNA that has an anticodon
on one side and an amino acid on the other side

9. What are the steps of translation?
1) The mRNA transcript goes to the ribosome,
and the ribosome holds it in place. One of
the codons on the mRNA is in the middle of
the ribosome.
2) A tRNA molecule pairs up with the codon
that’s in the middle of the ribosome; if the
anticodon on the tRNA matches with the
codon on the mRNA, the tRNA will attach to
the mRNA.

10. Processing Piece:
• Illustrate the first 2 steps of translation.

11. What are the steps of translation?
3) Another tRNA pairs with the next codon, and
the 2 amino acids are joined together.
4) One by one, all the codons are translated into
amino acids until the ribosome reaches the stop
codon, resulting in a polypeptide chain (a chain
of amino acids) which is folded together to
make a protein.

12. Processing Piece:
• Illustrate the last 2 steps of translation.

13. What is a start codon?
• A codon (AUG) that tells the ribosome “start
translating here;” it will be translated into the first
amino acid (methionine).
What is a stop codon?
• A codon (UAA or UAG) that tells the ribosome “stop
translating here.”

14. Processing Piece:
Draw a picture of a gene. Show where you
would find the start codon and the stop codon.

15. What is a codon chart?
• A chart that tells you what amino acid will come
from a codon on the mRNA when it is translated.

16. What is a codon chart?
• Example: If the mRNA is UAU, the amino acid will be
__________________________________.

17. What is a codon chart?
• Example: If the mRNA is UAU, the amino acid will be
tyrosine.

18. Circle each codon in the following
nucleotide sequences, then count how
many there are.
1) AUG CAC CGU UAA CUA
How many codons are there? ______

19. Circle each codon in the following
nucleotide sequences, then count how
many there are.
2) AUGCCUAUAGAC
How many codons are there? ______

20. Use your codon chart to translate each of
these mRNA transcripts into amino acids:
5) mRNA sequence: AUG UCA ACG UCA ACU
amino acid sequence: ___________________

22. Use your codon chart to translate each of
these mRNA transcripts into amino acids:
6) mRNA sequence: AUGCCGUAUAGA
amino acid sequence: ___________________

23. 8) DNA nucleotide sequence: TAC GAT AAT CGA CGA TTA ATC
mRNA nucleotide sequence: ___________________________
amino acid: ______________________________________

24. 9) DNA nucleotide sequence: TAC GAT GAA ATC AAT TCA
mRNA nucleotide sequence: ___________________________
amino acid: ______________________________________