Protein Synthesis Overview

DNA Replication:

  1. Assume that the following base sequence represents one side of a DNA molecule. In the space provided, FINISH the base sequence for the complimentary side of the DNA.

TAC-AGG-GTA-TAA-CCA-CGA-TCT-GGG-ATT

       __ A  T G  - _________________________________________________________________

  1. Define replication. _____________________________________________________________
  2. Where in the cell does replication occur? ___________________________________________
  3. When does replication occur? Why?   _____________________________________________

____________________________________________________________________________

Protein Synthesis:

  1. Using the DNA sequence below, FINISH the base sequence for the messenger RNA that the DNA would code for.

    TAC-AGG-GTA-TAA-CCA-CGA-TCT-GGG-ATT

     (mRNA) AUG - ______________________________________________________________

  1. Define transcription.  __________________________________________________________ ____________________________________________________________________________
  2. Where does transcription occur in the cell? _________________________________________

Given: The mRNA code is read three bases at a time.

  1. Define codon. ________________________________________________________________
  2. How many codons are in the mRNA molecule from Question 5? ________________________
  3. Define translation. ____________________________________________________________ ____________________________________________________________________________
  4. Where does translation occur? ___________________________________________________
  5. Define anticodon. _____________________________________________________________
  6. How many tRNA anticodons are needed to correspond with the mRNA sequence from Question 5? _________________________________________________________________
    1. Hint: How many codons are there in question 5?  ___________________________
    2. Hint:  How many anticodons should there be for each codon?  ______
  7. Write out the sequence of the anticodons that would match the mRNA from Question 5. Put a hyphen between each anticodon. _______________________________________________________________________

 

  1. Now that you know what anticodons are coming to the ribosome (in question 14), use the chart below to identify which amino acids the anticodons are going to bring with them.

 

REMEMBER THE TABLE BELOW IS MADE TO LOOK UP THE INGREDIENTS IN THE RECIPE, THE mRNA (refer to question #5).   List the amino acids below in the order that they would be put together.  

 

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  1. What is the amino acid for the DNA* code CTT? ______________________________________

What is the amino acid for the DNA* code GTT? ______________________________________

Does the amino acid change if the DNA code mutates from the code CTT to GTT? ___________

  1. What is the amino acid for the DNA code CCA? _______________________________________

What is the amino acid for the DNA code CCG? _______________________________________

Does the amino acid change if the DNA code mutates from the code CCA to CCG? ___________

  1. Look at the chart. How many amino acids have only one codon? ___________________________

List those amino acids below.  ______________________________________________________

  1. If an amino acid only appears on the chart once, what will happen if there is a mutation in the code for that amino acid? ______________________________________________________________
  2. For the amino acids that are on the chart more than once, it is possible that a mutation may not change the amino acid that is being coded for? _________________________________________
  3. Which amino acids on the table below are LEAST likely to change if there is a mutation? _______

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The Genetic Code (mRNA)*

 

 

 

FIRST BASE

A

Lysine

Lysine

Asparagine

Asparagine

Arginine

Arginine

Serine

Serine

Isoleucine

Methionine

Isoleucine

Isoleucine

Threonine

Threonine

Threonine

Threonine

A

G

U

C

 

 

 

 

THIRD BASE

G

Glutamic acid

Glutamic acid

Aspartic acid

Aspartic acid

Glycine

Glycine

Glycine

Glycine

Valine

Valine

Valine

Valine

Alanine

Alanine

Alanine

Alanine

A

G

U

C

U

“Stop” codon

“Stop” codon

Tyrosine

Tyrosine

“Stop” codon

Tryptophan

Cysteine

Cysteine

Leucine

Leucine

Phenylalanine

Phenylalanine

Serine

Serine

Serine

Serine

A

G

U

C

C

Glutamine

Glutamine

Histidine

Histidine

Arginine

Arginine

Arginine

Arginine

Leucine

Leucine

Leucine

Leucine

Proline

Proline

Proline

Proline

A

G

U

C

 

A

G

U

C

 

 

 

SECOND BASE