1. The DNA Connection

2. Chromosomes are made of DNA

3. The DNA Code

4. Each chromosome contains thousands of genes.

5. The sequence of bases in a gene forms a code

6. Every 3 Letters is called a CODON
Code = protein

7. DNA carries the codes

8. DNA
Deoxyribonucleic Acid (DNA)
Double Stranded

9. DNA Bases
Purines:
1. Adenine (A)
2. Guanine (G)

10. Pyridimines
1. Cytosine (C)
2. Thymine (T)

11. DNA Base Pairing
A=T
G C

12. RNA Base Pairing
A=U *Uracil
There is NO “T” in RNA
G C

13. Transcription

14. The process by which RNA is made from DNA
Occurs in the Nucleus

15. Since DNA is too big to fit through the nuclear pores, messenger RNA is used to “read” DNA

16. RNA
Single Stranded
Same bases as DNA EXCEPT instead of T RNA contains U

17. After transcription mRNA leaves the nucleus and attaches onto a ribosome

18. Translation

19. The message is translated into an amino acid sequence
Occurs on ribosomes

20. Every 3 Letters is called a CODON
Code = protein

21. Requires tRNA to translate the code

22. tRNA can only read 3 mRNA codes at one time (codon)

23. The Genetic Code
The Codon codes for which amino acid is to be made

24. Amino Acids – the building blocks of proteins

25. mRNA codon
UAC
Translated Code
Tyr

28. DNA Sequence:
A T G C A A T G C
U A C G U U A C G

29. RNA Sequence:
UAC GUU ACG
Amino Acids Produced:
Tyr – Val – Thr

32. DNA Mutations

33. Substitution

34. Deletion

35. Addition