1. DNA and Genes
Chapter 11 pgs

2. Take out 1 sheet of paper and write both lab partners names on it
Take out 1 sheet of paper and write both lab partners names on it. Discuss and answer the questions from the powerpoint on the paper
Textbook pg. 280
1. Pick one of the 3 bullet points under “What You’ll Learn” and explain what you think it means.
2. Why is DNA important?
3. Explain how the characteristics of the Shetland pony relate to its DNA?

3.  History of DNA
1800’s Mendel determined that offspring inherited traits from parents
1944 Biomolecule that was involved with heredity was DNA (originally proteins were thought to pass on traits because DNA was too simple)
SCIENCE IS TENTATIVE

4. Rosalind Franklin and Maurice Wilkins took diffracted photographs of DNA
X-rays were passed through DNA crystals, the X-rays were bent by the atoms in the DNA molecule producing an image of the shape

5. 1953 Watson & Crick developed a model of DNA using the diffraction photographs
Double Helix = DNA comes in 2 long strands that wrap around each other, “spiral staircase”

6. Textbook pg. 283
Look at figure 11.2 (don’t forget to read the caption!)
4. What is another analogy used for the shape of DNA (besides a spiral staircase)?

7.  Why is DNA so important?
DNA is known as “blueprint of life”
DNA contains instructions for making proteins within the cell
Genes are on our chromosomes, chromosomes are made of DNA

8. Turn to page 281 5. List 3 places in your body that contain proteins
Read the paragraph with the heading What is DNA?
5. List 3 places in your body that contain proteins
6. Enzymes are a type of protein. Why do we need them?

9. Why is DNA so important?
Important for all life on Earth, makes each individual plant or animal unique
Helps us understand diseases better & find potential cures
Better food crops

10.  DNA Nucleotides
DNA is a nucleic acid made from subunits called nucleotides
Nucleotide = 3 parts: five-carbon sugar, phosphate group, nitrogenous base
Deoxyribose = the sugar in a DNA nucleotide

11.  How the Double Helix stays together
phosphates
Double Helix has two strands that twist together
One strand of DNA is like one half of a zipper
The backbone of the molecule is alternating phosphates and deoxyribose sugar
The teeth are nitrogenous bases
deoxyribose
bases

12. One strand of DNA (half of a zipper) is a polymer of nucleotides
One strand of DNA has millions of nucleotides

13.  Nitrogenous Bases DNA has four different bases Cytosine C Thymine T
Adenine A
Guanine G

14. 2 kinds of Nitrogenous Bases
Purines = double ring bases, A and G
Pyrimidines = single ring bases, T and C

15.  Complementary Bases
Nitrogenous bases on the 2 strands of DNA pair up with one another
Cytosine pairs with Guanine with 3 (triple) Hydrogen Bonds
Adenine pairs with Thymine with 2 (double) Hydrogen Bonds

16. Textbook pg. 283 Read the Problem-Solving Lab 11.1
Answer the 3 “Thinking Critically” questions. These will be questions numbered 7-9 on your paper.

17.  DNA Model