Transcript Revealing the Genetic Code

Revealing the Genetic
Code
Protein Synthesis
Genetics
Q: How do genes (segments of DNA) determine
genetic traits?
A: one gene  one protein
Examples??
The secret of genes
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Gene = sequence of nucleotides (bases)
Protein = sequence of amino acids
Sequence of bases determines  sequence of
amino acids (protein’s primary structure)
Protein’s primary structure determines  its
secondary & tertiary (3D) structures
Protein’s 3D structure determines its function!!
Puzzle
Q: How do four bases (nucleotides) code for
twenty amino acids?
A: Triplet code!
Three letters  one amino acid
(codon)
But … codes (cookbooks) not permitted to leave
library!
4. Nucleic
acids
Deoxyribonucleic Acid (DNA)
- Information storage (Genetic material)
Transcription
Ribonucleic Acid (RNA)
- Intermediate carrier of information
Translation
Protein
- Molecule producing actions inside cell
Protein Synthesis: Prokaryote vs. Eukaryotes
Genetic Code
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1 base pair provides 4 choices
2 “ “
“
16 “
3 “ “
“
64 “
CATSATMAT
CATSATMAT
Question
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Which side of ladder is the code?????
(see board)
We know the code!!
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What amino acid does the DNA codon AAA
code for?
What amino acid does the mRNA codon AAA
code for?
What amino acid does the DNA codon CAT
code for?
What does the codon AUG do?
Genetic Code
NOW…
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You know enough to complete your practice
protein synthesis assignment!