280 likes | 740 Views
Aim: How does DNA store the genetic information?. DNA. D eoxyribo n ucleic a cid. What is DNA?. Carries the instructions for cell activities. Nucleic Acids. Nucleotides. DNA or RNA. Phosphate Sugar Base. Griffith’s Experiment:.
E N D
Deoxyribonucleic acid What is DNA? Carries the instructions for cell activities
Nucleic Acids Nucleotides DNA or RNA Phosphate Sugar Base
Griffith’s Experiment: Harmless strain of bacteria were “transformed” into a deadly strain and killed the mice. Griffith called the substance the “transforming factor”.
Avery’s Experiment: Was the transforming factor Protein or DNA? Heat treated deadly strain + harmless strain + protein destroying enzymes Transformed Bacteria Heat treated deadly strain + harmless strain + DNA destroying enzymes Bacteria did not Transform Concluded that DNA is the genetic material of the cell.
Hershey & Chase Experiment: Bacteriophage When only the phage protein coats were labeled, most of the radioactivity was detected outside the cell. When the phage DNA was labeled, most of the radioactivity was detected inside the cells.
What are these instructions? • GENES • How did we get our genes?
Where are genes found? Genes chromosomes nucleus (Largest) (Smallest)
What do our genes give us? Our characteristics or traits
46 How many genes do we have? ~30,000 on ______ chromosomes
How does DNA carry the genes? • The structure of DNA allows it to carry the genetic code • It is a double helix made of repeating nucleotides
What is a nucleotide made of? 4 types Deoxyribose Subunits of DNA
What bases make up the DNA ladder rungs? • Adenine • Thymine • Guanine • Cytosine (purine) (pyrimidine) (purine) (pyrimidine)
How do the bases pair up? All …. Teachers Go …. Crazy
What holds the DNA base pairs together? 3 Hydrogen Bonds Weak hydrogen bonds 2 Hydrogen Bonds
What in the DNA is unique in all organisms? The base sequence
What part of DNA carries the genetic code? The base sequence holds the genetic code. Each organism has a different sequence of bases
Let’s review Where is DNA found? What determines our traits? Where are genes located? What part of DNA carries the genetic code? Genes
SEMI CONSERVATIVE REPLICATION ONE OLD STRAND & ONE NEW STRAND