1. The sugar present in DNA is

ribose    dextrose     ribulose     deoxyribose

2. If ten percent of the bases in a molecule of DNA are adenine, what is the ratio of adenine to guanine in the same molecule?

1:1           1:2             1:3                 1:4

3. If a DNA molecule contains 10,000 bases, of which 18% are thymine, the number of cytosine molecules would be

1800                  3200                   6400                     8200

4. The structure of a nucleotide is shown below. Which of the diagrams that follow correctly shows two nucleotides joined together?

5. The diagram below shows the first two nucleotides in a DNA strand.

Which of the following statements about this DNA strand is correct?

Nucleotide 1 is the 3’ end with a phosphate group attached
Nucleotide 2 is the 5’ end and has a free hydroxyl group
Nucleotide 1 is the 5’ end with a phosphate group attached
Nucleotide 2 is the 3’ end with a phosphate group attached

6. Which of the following is a base pair normally found in DNA?

adenine and thymine                   guanine and adenine
thymine and guanine                   cytosine and adenine

7. Which diagram best shows the range of bases in DNA?

8. If a DNA molecule contains 4000 bases and 1200 of these are adenine (A), then the percentage of the bases which would be guanine (G) would be

12                    20                    28                          30

9. Considering the structure of double stranded DNA, what kinds of bonds hold one complementary strand to the other?

hydrogen          covalent       ionic             Van der waals

10. The percentage of adenine bases in a double strand of DNA is known. For how many of the other bases could the percentage be calculated?

none              one               two               three