1. Protein Synthesis Making Proteins

2. Review of DNA You have 46 chromosomes.
All those chromosomes are made of DNA.
What is DNA?

3. Review of DNA DNA is a double helix. Made up of 3 structures.
Phosphate
Sugar
Nitrogen Bases
A, T, C, G

4. Review of DNA DNA IS THE CODE FOR LIFE!
DNA is passed on from generation to generation.
MEIOSIS
DNA is copied when our bodies need to heal.
HOW DOES IT DO THIS?

5. Bodies  Cells  DNA Bodies are made up of cells
All cells run on a set of instructions spelled out in DNA

6. DNA  Cells  Bodies How does DNA code for cells & bodies?
how are cells and bodies made from the instructions in DNA

7. DNA  Proteins  Cells  Bodies
DNA has the information to build proteins
genes
proteins
cells
DNA gets all the glory, Proteins do all the work
bodies

8. How do proteins do all the work
proteins run living organisms
enzymes
control all chemical reactions in living organisms
structure
all living organisms are built out of proteins

9. Cell organization DNA DNA is in the nucleus
genes = instructions for making proteins
want to keep it there = protected
“locked in the vault”
cytoplasm
nucleus

10. Cell organization Proteins chains of amino acids
made by a “protein factory” in cytoplasm
protein factory = ribosome
cytoplasm
nucleus
build proteins
ribosome

11. Passing on DNA information
Need to get DNA gene information from nucleus to cytoplasm
need a copy of DNA
messenger RNA
cytoplasm
nucleus
build proteins
mRNA
ribosome

12. From nucleus to cytoplasm
transcription
DNA
mRNA
protein
translation
trait
nucleus
cytoplasm

13. DNA vs. RNA DNA RNA deoxyribose sugar nitrogen bases double stranded
G, C, A, T
T : A
C : G
double stranded
RNA
ribose sugar
nitrogen bases
G, C, A, U
U : A
C : G
single stranded

14. Transcription Transcription - Making mRNA from DNA
DNA strand is the template (pattern)
match bases
U : A
G : C
Enzyme
RNA polymerase

15. Matching bases of DNA & RNA
Double stranded DNA unzips T G G T A C A G C T A G T C A T C G T A C C G T

16. Matching bases of DNA & RNA
Double stranded DNA unzips T G G T A C A G C T A G T C A T C G T A C C G T

17. Matching bases of DNA & RNA
Match RNA bases to DNA bases on one of the DNA strands C U G A G U G U C U G C A A C U A A G C
RNA
polymerase U A G A C C T G G T A C A G C T A G T C A T C G T A C C G T

18. Matching bases of DNA & RNA
U instead of T is matched to A
TACGCACATTTACGTACGCGG
DNA
AUGCGUGUAAAUGCAUGCGCC
mRNA
ribosome U C A G

19. Because the RNA leaves to go outside the nucleus, we call it mRNA, or MESSENGER RNA
cytoplasm
protein
nucleus
ribosome U C A G
trait

20. How does mRNA code for proteins
mRNA leaves nucleus
mRNA goes to ribosomes in cytoplasm
Proteins built from instructions on mRNA
How?
mRNA U C A G aa

21. How does mRNA code for proteins?
TACGCACATTTACGTACGCGG
DNA
ribosome
AUGCGUGUAAAUGCAUGCGCC
mRNA ?
Met Arg Val Asn Ala Cys Ala
protein aa
How can you code for 20 amino acids with only 4 DNA bases (A,U,G,C)?

22. mRNA codes for proteins in triplets
TACGCACATTTACGTACGCGG
DNA
ribosome
codon
AUGCGUGUAAAUGCAUGCGCC
mRNA
AUGCGUGUAAAUGCAUGCGCC
mRNA ?
Met Arg Val Asn Ala Cys Ala
protein
Codon = block of 3 mRNA bases

23. The mRNA code There are only 20 amino acids
These amino acids code for ALL life!
strongest support for a common origin for all life
Code has duplicates
several codons for each amino acid
mutation insurance!
Strong evidence for a single origin in evolutionary theory.
amino acid
protein –
made of 4 amino acids

24. The mRNA code Start codon – code that starts the protein making
AUG
methionine
Stop codons – code that ends protein making
UGA, UAA, UAG
Strong evidence for a single origin in evolutionary theory. 24

25. How are the codons matched to amino acids?
Transfer RNA, or tRNA – brings the amino acid to the ribosome
On the amino acid is an anticodon
Anti-codon – block of 3 tRNA bases 25

26. How are the codons matched to amino acids?
TACGCACATTTACGTACGCGG
DNA
AUGCGUGUAAAUGCAUGCGCC
mRNA
codon
UAC
Met
GCA
Arg
tRNA
CAU
Val
anti-codon
amino acid
Anti-codon = block of 3 tRNA bases

27. Translation aa aa aa aa Translation – when mRNA makes the protein
The working instructions  mRNA
The reader  ribosome
The transporter  transfer RNA (tRNA)
ribosome
mRNA U C A G aa
tRNA G U aa
tRNA U A C aa
tRNA G A C
tRNA aa A G U

28. DNA mRNA protein trait From gene to protein tRNA transcriptionaa
transcription
translation
DNA
mRNA
protein
ribosome U C A G
tRNA aa
trait
nucleus
cytoplasm

29. cytoplasm
protein
transcription
translation
nucleus
trait

30. From gene to protein
protein
transcription
translation

31. Interactive

32. Interactive

33. Whoops! See what happens when your genes don’t work right!
Any Questions??