1. Chapter 12.1 DNA Structure Questions of the Day!!!
What is the biological molecule that stores genetic coding?
How could you tell if a molecule was a protein or if it was DNA? (think about their structures)
Understanding the structure of DNA, where in the molecule do you think the important genetic information is held? Why would it be held there?

2. Chapter 12.1 DNA Structure DNA is DeoxyriboNucleic Acid
DNA is made of a chain of repeating nucleotides. (stores genetic information)
DNA holds the genetic information that is used to make proteins...which make up all of YOU!

3. Chapter 12.1 DNA Structure
Nucleotides are comprised of 3 parts (Review Ch. 6)
a. Sugar (pentose…think pentagon)
b. Phosphate
c. Nitrogen containing BASE
The phosphate and sugar is IDENTICAL ON ALL NUCLEOTIDES

4. Chapter 12.1 DNA Structure Variation in nitrogenous (nitrogen) base
Combinations of the bases provide unique instruction for all organisms.
Variation of the bases ( Categories )
Purine – Bases with 2 rings – Adenine and Guanine
Pyrimidine – Bases with 1 ring – Cytosine and Thymine
Variation in nitrogenous (nitrogen) base
A = adenine
T = Thymine
G = Guanine
C = Cytosine

5. Chapter 12.1 DNA Structure Bases will pair together
Adenine (A) + Thymine (T)
Guanine (G) + Cytosine (C)
Purine + Pyrimidine

6. Chapter 12.1 DNA Structure DNA is a double helix 2 strands that twist
“Twisted Ladder”
Helix is a backbone of sugar and phosphate (sides of ladder)
Base pairs (A, T, G, C) hold the sides of the ladder together (rungs)

7. Chapter 12.1 DNA Structure
What do the grey rings (with red) and yellow dots represent?
What do the blue and red portions in the middle represent?
Where is the genetic information?

8. Chapter 12.1 DNA Structure

9. Chapter 12.1 DNA Structure
Watson and Crick won the Nobel Prize for Science by figuring out the shape of DNA through their experiments. They took the xray work of Rosalind Franklin to determine the shape of DNA

10. Chapter 12.1 DNA Structure TASKS!!!
Draw and label a DNA molecule listing where the genetic code is and where the sugar phosphate backbone is.
List the base pairs categorizing them as Purines or Pyrimidines. Also pair the ones that go together.
DNA video game!