Structure of DNA Questions
Name: _________________
1. What do the letters DNA stand for?
2. Two scientists are given credit for discovering the structure of DNA. What are the names of those two scientists?
3. DNA is a polymer, which means that is made up of many repeating single units called monomers. What are the
monomers that make up DNA called have a specific name. What are they called?
4. There are four different variations of these monomers created by adding one of four different bases, what are the
names of these bases?
5. These bases are of two different types of molecules: purines and pyrimides. Purines have
_______________________ ring(s) in their structure, and pyrimidines have _______________________ ring(s)
in their structure.
6. The two bases that are purines are:
7. The two bases that are pyrimidines are:
8. What two parts of the nucleotide make up the backbone structure in the DNA molecule?
9. Looking at the structure on adenine and thymine in the picture to the right, which
atoms in each of the bases are involved in forming hydrogen bonds? Circle the
atoms in the nucleotide bases.
10. How many 5’ ends are there in this molecule of DNA?
11. Are the 5’ ends on the same strand or different strands?
12. Chargaff’s rule states that the DNA of any species contains equal amounts of
_______________________ & _______________________ and also equal
amounts of _______________________ & _______________________.
13. Based on this information, scientist could predict that the base
_______________________ pairs with _______________________ and the
base _______________________ pairs with _______________________ in the
formation of the DNA molecule. This is called ___________________ base pairs.
Thus one strand of DNA is complementary to the other strand.
14. Wilkins and Franklin studied the structure of DNA using
_______________________, a technique to examine molecules, and helped
Watson and Crick determined that the shape of the molecule was a
_______________________ _______________________.
15. Write the complementary sequence to following DNA strand:
AA T TC GCCGG T AT TAG A CGT T
| | | | | | | | | | | | | | | | | | | | |
16. What type of bond is found in the backbones of the
DNA molecule?
17. Label the 3 parts of the nucleotide to the right:
18. Use the image at the right to complete the following:
a. Label the sugar and phosphate.
b. Label the bases that are not already labeled.
c. Number the Carbons in the Deoxyribose molecule.
d. Label the 3’ and 5’ ends of the molecule.
Biotechnology -
Utah Health Sciences Education
1