10HS Biology_Revision Session 1_Classwork
Revision Session 1 – Sections 8.1 – 8.3
1. Complete the table of researchers and their experiments that contributed to the understanding of
DNA as genetic material
Scientists,
Year
Frederick
Griffith, 1928
Oswald
Avery, 1944
Alfred
Hershey &
Martha
Chase, 1952
Experiment
Outcome
Conclusion
10HS Biology_Revision Session 1_Classwork
2. What did these scientists contribute to our understanding of DNA structure?
Scientists
Contributions
Franklin & Wilkins
Erwin Chargaff
Watson & Crick
3. Work out the missing percentages
Organism
Human
Chicken
Rat
E. coli
%A
29.3
28.0
28.4
%G
20.7
21.4
26.9
4. How many hydrogen bonds are between A and T? C and G?
5. Label the nucleotide
1
2
3
%C
20.0
21.6
26.9
%T
30.0
10HS Biology_Revision Session 1_Classwork
6. Label the DNA strand
1
2
3
4
5
6
7. Identify the two types of bonding in the DNA strand and where they are found
8. Complete the complementary strand
A
A
T
T
G
G
C
C
G
G
10HS Biology_Revision Session 1_Classwork
9. Compare and contrast purines and pyrimidines
Purines

Pyrimidines

10. Complete the sentences
a. DNA replication occurs in the ________ of eukaryote cells
b. DNA Replication occurs during __________ of the cell cycle
c. It is important because DNA must divide before _______ and ________.
11. List the steps of DNA replication shown below
1
2
3
4
5
10HS Biology_Revision Session 1_Classwork
12. What do these enzymes do during DNA replication?
Helicase
Primase
DNA polymerase
Ligase
13. Complete these sentences
a. DNA polymerase can only synthesize _______ direction
b. On the ________ strand, DNA polymerase is moving away from the __________ fork
c. Therefore, it must constantly return to copy newly separated stretches of DNA called
________________
14. Which of these represents semi-conservative replication? Why?
15. What is the benefit of proofreading?