1. Enzyme Review

2. D.

3. The human body maintains a temperature of around 98
The human body maintains a temperature of around 98.6 degrees at all times. Enzymes are involved in almost every chemical reaction in the body. Which of the following describes the connection between these two statements? A. Enzymes function best at a specific temperature. B. The body needs to be warm to prevent hypothermia. C. The body is kept relatively warm to prevent too much enzyme action. D. There is no connection between the two statements. A.

4. The enzyme lactase will break down the sugar lactose into which of the following components? 
A. monosaccharides
B. nucleic acids
C. amino acids
D. phospholipids

5. DNA Replication
SC.912.L Describe the basic process of DNA replication and how it relates to the transmission and conservation of the genetic information

6. DNA REP
Objective: Recall the components and structure of DNA and Describe the process of DNA replication and its role in the transmission and conservation of genetic information.
EQ: How does the process of DNA replication allow for information to be retained and transferred?

7. Developments in DNA Structure
Erwin Chargaff: determined that different organisms have the same 4 bases but in different ratios
Also noted that the amounts of C and G were relatively the same; A and T were also the same
James Watson, Francis Crick: developed accurate model of DNA’s double helix structure
Used info from x-ray crystallography
Rosalind Franklin, Maurice Wilkins: looked at the structure of DNA using x-ray crystallography

8. Structure of DNA DNA is made up of a long string of nucleotides
Each nucleotide has 3 parts:
Phosphate group
Nitrogen-containing base
Deoxyribose (sugar)
phosphate group
deoxyribose (sugar)
nitrogen-containing
base

9. Structure of DNA Quick review! DNA and Nucleotides…
Which is the polymer and which is the monomer?
Nucleic acids (DNA) = polymer
Nucleotides = monomer

10. Structure of DNA
The only difference between the nucleotides is the nitrogen-containing base
Pyrimidines (thymine and cytosine) have single rings
Purines (adenine and guanine) have double rings

11. DNA Structure Sugar-phosphate backbones
Single-ring bases pair with double-ring bases
4 Nucleotides (bases):
Adnine (A) Guanine (G)
Cytosine (C) - Thymine (T)
Base Pairing Rules:
A pairs with T
C pairs with G
Forms a double helix
(spiral ladder)
Notice that G and C look similar and pair together!

12. Base Pairs
Nucleotides in a single strand are joined by covalent bonds (sugar and phosphate)
Nucleotides on separate strands (base pairs, two stands) are held together by hydrogen bonds
hydrogen bond
covalent bond

13. Base-Pairs Practice
Which base would be paired with…
Adenine

14. Base-Pairs Practice Which base would be paired with…
Adenine pairs with thymine

15. Base-Pairs Practice
Which base would be paired with…
Cytosine

16. Base-Pairs Practice Which base would be paired with…
Cytosine pairs with guanine

17. Base-Pairs Practice
Which base would be paired with…
Thymine

18. Base-Pairs Practice Which base would be paired with…
Thymine pairs with adenine

19. Base-Pairs Practice C – T – A – G - G
Write the sequence of nucleotides that would be paired with the first strand
C – T – A – G - G

20. Base-Pairs Practice C – T – A – G – G G – A – T – C – C
Write the sequence of nucleotides that would be paired with the first strand
C – T – A – G – G
G – A – T – C – C

21. DNA Replication
DNA only stores genetic information
Specialized proteins are used to replicate the DNA
Each single strand of DNA can be used as a template for the other strand
During replication, the incoming nucleotides are matched with their partner on the original strand
All cells have a complete set of DNA
Different types of cells express the genes differently, but all cells still have ALL DNA

22. Process of Replication
Enzymes unzip the double helix at origins of replication
- Occurs in multiple locations on the eukaryotic strand of DNA

23. Process of Replication
2. As lone nucleotides are exposed by the unzipping of the DNA, enzymes (DNA Polymerases) pair free-floating nucleotides in the nucleus with the bases on the original strand
DNA polymerase
new strand
nucleotide

24. Process of Replication
3. The result is two identical strands of DNA - One side of each strand is the original strand (template) - The other side of the strand is the newly-synthesized complementary strand
original strand
new strand
Two molecules of DNA

25. How do you eat DNA-spaghetti?
With a replication fork 

26. Semiconservative Replication
The process of DNA replication is semiconservative
Each DNA strand is half original, half replicated
Conservative replication would have one copy of the DNA with both original strands; the other copy of DNA would have both new strands
Proofreading: enzymes (DNA polymerases) check for errors, replace mismatched nucleotides

27. Think, Pair, Share
Why is it important for the process of DNA replication to be accurate?
Where is DNA in the cell? Where does DNA rep take place?

28. Left Side Activity! Modeling the structure of DNA… WITH CANDY!!!
Using twizlers, gummy bears, and toothpicks, go through the process of DNA replication.
C- level 2, talk to your table partner
H- ask three before me
A- using provided materials, go through the process of DNA Replication
M- Remain seated in your assigned seat
P- create and replicate your own DNA strand
Success

29. Exit ticket
Clear your desk of everything except something to write with and your DO NOW.