1. DNA & RNA

2. What we already know... The nucleus holds the DNA
Eukaryotes have linear (in a line) DNA
Prokaryotes have circular DNA
DNA is copied during Interphase of the Cell Cycle

3. What you may also know...
Traits are distinguishing features or characteristics
Traits are passed from parent to offspring
Traits are passed on through genes
Genes are specific sections of DNA
In sexual reproduction, offspring get half their genes from each parent

4. DNA is INFORMATION DNA = Deoxyribonucleic acid
Molecule that stores information
Contains instructions for making proteins
Similar to a cookbook which contains instructions for making a cake

5. Check for understanding:
What is a trait?
When is DNA copied?
What is a gene?

6. Check for understanding:
What is a trait?
distinguishing features or characteristics
When is DNA copied?
during Interphase of the Cell Cycle
What is a gene?
specific sections of DNA

7. DNA Structure Double Helix -Shaped like a twisted ladder
Formed from Nucleotides which are made of:
Phosphate
Sugar (deoxyribose)
Nitrogen base
Latin Bonus: Any word in science ending in “-ose” means it is a sugar (ex- glucose, fructose, deoxyribose)

8. DNA Structure Side rails of ladder are sugar-phosphates
Rungs of ladder are formed by 2 nitrogen bases coming together
4 Nitrogen bases (GCAT):
Guanine
Cytosine
Adenine
Thymine
Let's learn the DNA song! As you listen, write the lyrics in your notes

9. Base Pair Rule of DNA Structure
These Nitrogen Bases ALWAYS pair together!
Guanine - Cytosine
Adenine - Thymine
Let's review!

10. Check for understanding
What are the 3 parts of a nucleotide?
What are the 4 bases and how do they pair together?

11. Check for understanding answers
What are the 3 parts of a nucleotide?
Sugar, Phosphate, Nitrogen base
What are the 4 bases and how do they pair together?
Guanine - Cytosine
Adenine - Thymine

12. So what’s RNA? RNA is similar to DNA except RNA has:
RNA explained
RNA is similar to DNA except RNA has:
RIBOSE sugar instead of deoxyribose sugar.
URACIL instead of thymine.
Has a SINGLE STRAND.
Another DNA & RNA song

13. RNA is needed to make PROTEINS

14. Try this: Copy this DNA sequence: A - T - G - A - C - G
Write the base pair letters of the 2nd strand of DNA.
Let's build a DNA molecule on the board!

15. Check your answer: Copy this DNA sequence: A - T - G - A - C - G
Write the base pair letters of the 2nd strand of DNA.
T - A - C - T - G - C

16. History of DNA discovery
1952 Rosalind Franklin takes X-Ray photograph of DNA
1953 James Watson & Francis Crick use Franklin’s images to describe the structure of DNA
1962 Watson, Crick, & Wilkins win Nobel Prize. Franklin died in 1958 so she did not get recognized for her part.