The document summarizes the process of protein synthesis in 3 steps: (1) Transcription of DNA into mRNA in the nucleus, (2) Export of mRNA from the nucleus into the cytoplasm, (3) Translation of mRNA by ribosomes into a polypeptide chain that folds into a protein.

1. In this slide, notice how we only have one organelle, the nucleus, within the cell. Protein
synthesis starts in the nucleus of the cell.

2. Chromosomes

3. Chromosomes
DNA Strands
This slide shows the location of the DNA strands. They are located on
the chromosomes.

4. DNA Double Helix
RNA Polymerase
mRNA Strand
In this slide, RNA polymerase unwinds the DNA and creates the mRNA copy. The mRNA
copy is made until the RNA polymerase reaches the termination sequence.

5. C C T A G C G T T T A C T G C T G T A A T T C G C T A A T T
G G A U C G C A A A U G A C G A C A U U A A G C G A U U A
A
Coding Region Termination Sequence
Start Codon
Promoter Region
This slide shows the DNA strand unwound while the RNA polymerase has completed
the mRNA copy of the DNA strand. When this happens, the RNA polymerase and the
mRNA strand fall off of the DNA strand and leave through the nuclear pore. (shown
next slide)

6. mRNA Strand
The final step of transcription is the mRNA strand goes through a
nuclear pore to the cytoplasm. This is the start of the last step in
Protein Synthesis, translation.

7. Ribosome
Nucleus
DNA mRNA Strand
Strand
Cytoplasm

8. Ribosome
Codon
G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A

9. G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
The Ribosome begins to read the mRNA sequence.

10. Start Codon
G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
U A C
Anticodon
tRNA
Amino Acid
(Methionine)

11. G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
U A C
Methionine
The anticodon bonds with the start codon when the ribosome reads it.

12. G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
U A C U G C
Peptide bond
Methionine Threonine
The Ribosome reads the next codon and another tRNA with a complementary anticodon
binds. Then, the Ribosome promotes a chemical reaction to join the two amino acids
together called a peptide bond.

13. G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
U G C
Threonine
Methionine
As the Ribosome continues down the mRNA strand, the first tRNA falls off,
leaving the amino acid.

14. G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
U G C U G U
Methionine Threonine
Threonine
New tRNA continues to come in and bind to the
Ribosome and the amino acids bond.

15. Stop Codon
G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
A A U
This continues until the Ribosome
reads the Stop Codon.
Leucine
Threonine
Threonine
Methionine

16. G G A U C G C A A A U G A C G A C A U U A A G C G A U U A A
U C G
Serine
Leucine
Threonine
Methionine Threonine

17. A U G A C G A C A U U A A G C G A U G A A G G A U C G U A A
A U U
The ribosome reached the stop codon and has now
stopped making amino acids.
Glycine Serine
Threonine Glutamic Acid
Serine
Stop
Aspartic Acid
Leucine
Methionine Threonine

18. A U G A C G A C A U U A A G C G A U G A A G G A U C G U A A
The ribosome falls off of the mRNA strand and the tRNA
falls off the ribosome.
Glycine Serine
Threonine Glutamic Acid
Serine
Stop
Aspartic Acid
Leucine
Methionine Threonine

19. The amino acid chain groups together closely to create a three-
dimensional structure by the order of which the amino acids
where made. This is now a protein.

20. Summary:
In the nucleus of the cell, RNA polymerase unwinds the DNA double helix structure and
creates the mRNA copy for transcription. The starting codon is where the RNA polymerase
knows where to start the mRNA strand. The termination sequence is the codon that
signals the RNA polymerase to stop copying the DNA strand. The mRNA strand then leaves
the nucleus into the cytoplasm where translation starts. In the cytoplasm of the cell,
where a ribosome reads the mRNA strand and creates the amino acid chain
complementary to the strand. The amino acid chain folds up into a three-dimensional
structure called a protein.