1. DNA RNA Protein Synthesis Review

2. Contributors Watson and Crick Rosalind Franklin Chargaff
Hershey and Chase
Avery and Griffith

3. Role of DNA in the cell
Copy info
Store info
Transmit info

4. DNA Stands for Deoxyribonucleic acid Structure Double helix
Composed of what monomers?
Nucleotides
These are composed of
Phosphate
5 carbon sugar (deoxyribose)
Nitrogen bases
These 4 are
Adenine
Guanine
Cytosine
Thymine

5. Bases divided into two categories
Purines
Adenine and guanine
Two rings
Pyrimidines
Thymine and cytosine
Not on test, just for your personal knowledge

6. DNA replication Step 1 Helix unzips Enzyme? Helicase
What bonds are broken?
Hydrogen
Step 2
Each strand becomes a template for a new strand
What enzyme builds?
DNA polymerase
Step 3
DNA polymerase does what now?
proofreads

7. RNA structure Strand #? One Can it leave the nucleus? Yes
Monomers made of
Ribose (5 carbon sugar)
Phosphate
Nitrogen bases
A, G, C, and Uracil

8. Three kinds of RNA mRNA, rRNA, tRNA Messenger RNA
Moves the message, the recipe for the protein
Ribosomal RNA
Builds the ribosomes
Transfer RNA
Carries the amino acids to the ribosome according to the recipe

9. Transcription What is it? DNA to RNA Begins at Promotor sequence
Ends at?
Terminator sequence
This strand is ______________ to the original DNA strand
complementary

10. Translation What is it? RNA to protein Read in codons, which are
Groups of 3 nitrogen bases
Each one codes for a specific
Amino acid
Each sequence begins with
Start codon, AUG
Which codes for
Methionine
Each stops with a
Stop codon

11. Process of translation
Ribosomes read
mRNA
tRNA brings
AA’s and matches them with the correct codon on mRNA
tRNA’s anti-codon is
complementary to mRNA’s codon
tRNA enters the ribosome to drop off
Amino Acids
AAs binds together to form the
growing polypeptide

12. Steps to translation Initiation: begins at AUG (start codon)
Elongation:
AA’s are added to the polypeptide chain until reaching a stop codon
Peptide bonds are formed between each pair of AA’s
Termination
a stop codon (codes for a tRNA with no amino acid) is read

13. Gene Regulation and Expression
Not all genes are expressed
In every cell
Or at the same time.
In Eukaryotes
transcription factors
control the expression of genes.
Cell Specialization
genes are turned on or off depending on cell type, for example liver cells will produce different proteins than muscle cells.

14. Mutations Mutation: change in the nucleotide sequence Types:
Gene Mutations:
Change 1 gene
Point mutations
when one base is substituted for another
Frameshift mutations
when a base is added or deleted (the entire reading frame is changed)

15. What do mutations cause? Diversity! Genetic Disease Sickle cell anemia
What causes mutations?
Spontaneous mistake (natural)
Mutagens a physical or chemical agent
What do mutations cause?
Diversity!
Genetic Disease
Sickle cell anemia
Cystic fibrosis
Huntington’s disease
Cancer

16. Are mutations always bad?
NO!
When can they be good?
Evolution, biodiversity