1. Protein Synthesis

2. Learning Targets
Summarize the process of transcription.
Identify the genetic code and explain how it is read.
Summarize the process of translation.

3. Review!
Proteins are polymers made up of 20 different amino acids (a.a.)

4. Review! Proteins have MANY different functions
Enzymes to help control/speed up chemical reactions
Help to build and repair cell structures
Determine the structure & function of living organisms

5. Review!
DNA contains the sequence of nucleotides that codes for the synthesis of proteins.
DNA is found in the nucleus
Proteins are made on ribosomes out in the cytoplasm
HOW CAN INFORMATION FROM THE NUCLEUS GET TO THE RIBOSOME?
RNA! – mRNA is used to move
information from the DNA to
ribosomes (TRANSCRIPTION!)

6. Translation
The process of converting the information in the nitrogen base sequence of mRNA into a sequence of amino acids that make up proteins
Occurs in the RIBOSOMES

7. Translation 1. mRNA attaches and passes through a ribosome
2. First codon on mRNA moves into position
3. tRNA (transfer RNA) starts bringing the appropriate amino acids to ribosome

8. Translation 5. mRNA slides along ribosome to next codon
4. ANTICODON of the tRNA matches to the correct codon on mRNA
5. mRNA slides along ribosome to next codon

9. Translation
6. A new tRNA molecule with the next amino acid pairs with mRNA codon
7. When the 1st and 2nd amino acids are in place, a PEPTIDE BOND forms between them – creating a protein

10. Translation
8. Transfer RNA released to pick up amino acid to be recycled
9. Process continues until a “stop” codon is reached & a chain of amino acids is formed = PROTEIN
Protein Synthesis Animation

11. Let’s Review…again!
Transcription and Translation Simulation

12. Decode the following
If the coding DNA strand contained the following sequence: TAC CGA TTG ACT
What would the mRNA strand be?
AUG GCU AAC UGA
What would the tRNA sequence be?
UAC CGA UUG ACU
What would the amino acid sequence be?
(base it on the mRNA strand!)
methionine, alanine, asparagine, “stop”