Name ______________________________________
Date ______________
Class __________
DNA Replication Worksheet
Use the diagram to answer the questions to the right.
1. Which of the labeled DNA strands are the parent strands? ____________
2. Which of the labeled strands are newly synthesized DNA? ___________
3. What nucleotide will be added to strand B next?
___________
4. What nucleotide will be added to strand C next?
___________
5. What holds the bases in strands A and B together?
___________
6. What holds the backbone of strand A together?
___________
The diagrams below show the steps of DNA replication. Put the steps in order (1-3).
7.
__________________
8. __________________ 9. ___________________
10. What is the first step in DNA replication? ______________________________________________________
__________________________________________________________________________________________.
11. What enzyme matches the bases of free nucleotides to the bases on the parent strand?
______________________________________________
12. If the DNA double helix were a twisted ladder, what would the sides of the ladder be made of?
______________________________________________________________
13. What would the rungs of the ladder be made of? ______________________________________________
Complete the table below.
NUCLEOTIDE BASE
14.
ABBREVIATION
T
COMPLEMENTARY BASE
18.
15.
C
19.
16.
A
20.
17.
G
21.
22. The three main types of RNA are ____________________, _____________________, and ______________.
23. Copying part of a nucleotide sequence of DNA into a complementary sequence in RNA is called
_________________________________.
24. An enzyme that binds to DNA during transcription is RNA _____________________________.
25. During the process of __________________________, the information carried by mRNA is used to
produce proteins.
26. Each tRNA molecule contains three unpaired bases, called the ___________________________, which
ensure that amino acids are added in the correct sequence.
27. How are DNA and RNA similar and how are the different? ______________________________________
___________________________________________________________________________________________
Completion Choose the words that correctly complete the following sentences.
28. During DNA replication, the DNA molecule __________________ (separates/combines) into two strands.
29. At the end of DNA replication, ______________________ (four/two) new strands of DNA have been
produced, giving a total of ___________________ (four/six) strands of DNA.
30. New DNA is replicated in strands complementary to old DNA because production of new DNA follows
the rules of ___________________________ (base pairing/the double helix).
Identifying Structures On the lines corresponding to the numbers on the diagram, write whether the strand
pointed to is an ORIGINAL strand or a NEW strand.
32.
31.
31. ____________________________
32. ____________________________
33. ____________________________
34. ____________________________
33.
34.