1. Happy Thursday….
Turn in the DNA homework sheet from Tuesday if you did not finish it in class.
Bellwork: Explain the steps of the DNA replication process. You must use all of the words below.
Double Helix, unzip, helicase, DNA polymerase, complementary, nucleotides, semi-conservative

2. Test tomorrow…
Review sheet Notes Power Points Extra Credit Open your Journal to page 38. Title that page Test Review. Number your page 1-25 (leave space)

3. DNA: Structure and Replication Hallway Practice

4. 1. What would the complementary strand of the DNA molecule shown below look like?

5. 1. What would the complementary strand of the DNA molecule shown below look like?
T A A G C C C T A T A A

6. 2. Scientists compared the DNA in four mammals shown to the right
2. Scientists compared the DNA in four mammals shown to the right. Based on the table, which two mammals are most closely related to each other?
Mammal
DNA Sequence 1
TCTCAACTACAA 2
TCTCAGCTGCAA 3
ACTCAGCTACAA 4
TCTCAGCTGCAG

7. 2. Scientists compared the DNA in four mammals shown to the right
2. Scientists compared the DNA in four mammals shown to the right. Based on the table, which two mammals are most closely related to each other?
Mammal
DNA Sequence 1
TCTCAACTACAA 2
TCTCAGCTGCAA 3
ACTCAGCTACAA 4
TCTCAGCTGCAG

8. 3.-4. In a sample of double-stranded DNA, 30% of the nitrogenous bases are thymine. What percentage of the nitrogenous bases in the sample are adenine? What percentage are guanine (in the same sample)?

9. 3.-4. In a sample of double-stranded DNA, 30% of the nitrogenous bases are thymine. What percentage of the nitrogenous bases in the sample are adenine? What percentage are guanine (in the same sample)?
If 30% is Thymine then 30% must be Adenine (base pairing rule).
The total percent of A and T would equal 60% (30% A + 30% T = 60%)
That leaves 40% total for C and G. We know they have to be equal so we split 40% in half (base pairing rule).
The percentage for C must be 20% and the percentage for G therefore must be 20%. 

10. 5. A single nucleotide of DNA is composed of which of the following substances?
adenine, guanine, and cytosine B.
hydrogen, a phosphate group, and adenine C.
ribose sugar, deoxyribose sugar, and thymine D.
deoxyribose sugar, a phosphate group, and a nitrogenous base

11. 5. A single nucleotide of DNA is composed of which of the following substances?
adenine, guanine, and cytosine B.
hydrogen, a phosphate group, and adenine C.
ribose sugar, deoxyribose sugar, and thymine D.
deoxyribose sugar, a phosphate group, and a nitrogenous base

12. 6. Which of the following statements describes each new molecule of DNA produced when DNA replicates? A.
Each new molecule is half the length of the original molecule. B.
Each new molecule has only the coding portions of the original molecule in its sequence. C.
Each new molecule contains one strand from the original molecule and one newly synthesized strand. D.
Each new molecule retains the A, C, and G bases in the DNA sequence but replaces the T base with U

13. 6. Which of the following statements describes each new molecule of DNA produced when DNA replicates? A.
Each new molecule is half the length of the original molecule. B.
Each new molecule has only the coding portions of the original molecule in its sequence. C.
Each new molecule contains one strand from the original molecule and one newly synthesized strand. D.
Each new molecule retains the A, C, and G bases in the DNA sequence but replaces the T base with U

14. 7-9. Identify the part of DNA indicated by the arrow.8

15. 7-9. Identify the part of DNA indicated by the arrow.8
Nitrogenous Base
Deoxyribose Sugar
Hydrogen Bonds

16. 10. For each statement below, indicate the biomolecule that is being described. (carbohydrate, lipid, protein, nucleic acid) A.
Store and transmit genetic information B.
Main component of the cell membrane C.
Speeding up biochemical reactions (catalyst) D.
Polysaccharide broken down for energy

17. 10. For each statement below, indicate the biomolecule that is being described. (carbohydrate, lipid, protein, nucleic acid) A.
Store and transmit genetic information (Nucleic Acid) B.
Main component of the cell membrane (Lipid) C.
Speeding up biochemical reactions (catalyst) (Protein/enzyme) D.
Polysaccharide broken down for energy (Carbohydrate)

18. 11. Which of the following models most accurately represents the structure of DNA? Explain why.B C

19. 11. Which of the following models most accurately represents the structure of DNA? Explain why.B C
Incorrect: bases on outside
Incorrect: shows two phosphates instead of one in backbone.
Sugar Phosphate Backbone, Antiparallel. Bases properly paired in the middle
Incorrect: Single strand instead of double

20. 12-14. Identify the structure indicated by the arrows below13 14 12

21. 12-14. Identify the structure indicated by the arrows below13 14
Nitrogenous Bases 12
Nucleotide
Sugar Phosphate Backbone

22. 15. Copy and complete the chart below
Monomer
Polymer
Carbohydrate
Fatty Acid
Protein
Nucleotide

23. 15. Copy and complete the chart below
Monomer
Polymer
Monosaccharide
Carbohydrate
Fatty Acid
Lipid
Amino Acid
Protein
Nucleotide
Nucleic Acid

24. 16. What information about DNA was discovered from the picture below?

25. 16. What information about DNA was discovered from the picture below?
This famous picture from Rosalind Franklin was the important because it gave the first real evidence for the double helix STRUCTURE of DNA

26. 17. The graph below shows how the activity of an enzyme changes over a range of pH values. What is the optimum pH for this enzyme to function in?

27. 17. The graph below shows how the activity of an enzyme changes over a range of pH values. What is the optimum pH for this enzyme to function in?
Optimum means “best”.
The Enzyme works “best” at a pH of 6.6

28. 18. Indicate whether the following statements are true or false.
Enzymes are recycled after each use, and can be used over and over again.
Enzymes reduce the activation energy required for chemical reactions.
Enzymes fit with multiple types of substrates.
Enzymes are specific and fit with only one type of substrate.

29. 18. Indicate whether the following statements are true or false.
Enzymes are recycled after each use, and can be used over and over again. T
Enzymes reduce the activation energy required for chemical reactions. T
Enzymes fit with multiple types of substrates. F
Enzymes are specific and fit with only one type of substrate. T

30. 19. Explain what biological process is occurring in the picture below.

31. 19. Explain what biological process is occurring in the picture below.
This is a picture of the DNA replication process

32. 20. A ring is analogous to a carbohydrate, just as a twisted ladder is analogous to ________.

33. 20. A ring is analogous to a carbohydrate, just as a twisted ladder is analogous to _DNA_______.
*Analogous means “similar to”

34. 21. Describe the function of both helicase and DNA polymerase as enzymes in DNA replication.

35. 21. Describe the function of both helicase and DNA polymerase as enzymes in DNA replication.
Helicase: unzips the double helix structure of DNA
DNA Polymerase: assembles the new complementary strand onto the original strand

36. 22. Why is DNA referred to as the common genetic code
22. Why is DNA referred to as the common genetic code? **Hint: What information is carried in the DNA molecule?**

37. 22. Why is DNA referred to as the common genetic code
22. Why is DNA referred to as the common genetic code? **Hint: What information is carried in the DNA molecule?**
All living things have DNA and the exact same four Nitrogenous Bases (ATCG). The sequence of the bases determines the “code” for that organism.

38. 23. Which of the following features in DNA is most important in determining the traits of an organism? A.
the direction of the helical twist B.
the number of deoxyribose sugars C.
the sequence of nitrogenous bases D.
the strength of the hydrogen bonds

39. 23. Which of the following features in DNA is most important in determining the traits of an organism? A.
the direction of the helical twist B.
the number of deoxyribose sugars C.
the sequence of nitrogenous bases D.
the strength of the hydrogen bonds

40. 24. The statements below describe the function of an enzyme in the body. Which statement is true?
The enzyme increases the amount of time the light is visible.
The enzyme decreases the amount of energy required for the reaction to start.
The enzyme increases the number of sites on the substrate that must bind to oxygen.
The enzyme decreases the temperature of the environment inside the body.

41. 24. The statements below describe the function of an enzyme in the body. Which statement is true?
The enzyme increases the amount of time the light is visible.
The enzyme decreases the amount of energy required for the reaction to start.
The enzyme increases the number of sites on the substrate that must bind to oxygen.
The enzyme decreases the temperature of the environment inside the body.

42. 25. Enzymes usually end in the letters _____, while carbohydrates usually end in the letters _____.

43. 25. Enzymes usually end in the letters _ase_, while carbohydrates usually end in the letters _ose_.