DNA extraction from cheek cells protocol I mailed to you - DOC

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					                                         HHS Biology
          Name: _________________________________ Period: ___ Assign. #: _3__
          Date Due: ____________________         Score: ____/____

                        DNA Extraction Alternative
                             Lab Questions
1. Why is DNA so important in biology?

2. What is the function of DNA?

3. Where is DNA found in our bodies?

4. Draw a simple diagram of a cell, showing the cell membrane and the DNA in chromosomes
surrounded by a nuclear membrane.

5. Which of the following do you think will contain DNA? Explain your reasoning.
bananas __ concrete __ fossils __ meat __ metal __ spinach __ yeast __

6. List the steps in order as you perform the virtual DNA Extraction Lab:

Read Section 5.2 in your notes about DNA Replication.

Copying the Code
7. Why are the strands of a DNA molecule said to be complementary?

8. What is the first step in eukaryotic DNA replication?

9. If the base sequence on a separated DNA strand is CGTAGG, what will the base sequence on its
complementary strand be?

10. What enzyme joins individual nucleotides to produce the new strand of DNA?

11. What is a replication fork?

12. Does DNA replication take place in the same direction along both strands of the DNA molecule
that is being replicated? Explain your answer. (Hint: Look at the illustration of DNA replication in your
note packet.)

13. Make a sketch of the double helix of DNA. Show how it unzips for replication and how
complementary strands are built. Label the nitrogenous bases, replication fork, DNA polymerase, the
original strand, and the new strand.

14. Complete the table to compare and contrast DNA replication in prokaryotes and eukaryotes.

                                     Prokaryotes           Eukaryotes
 Location of DNA

 Amount of DNA

 Starting Point(s) for Replication

15. Is DNA replication always a foolproof process? Explain your answer.

16. Why is the pairing of bases during replication essential for the transmission of inherited traits from
parent to offspring?

Bonus Question (5 extra credit points): Suppose that DNA did not have a double helix structure, and
instead DNA was single-stranded. Imagine that a cell with this single-stranded DNA was ready to
begin cell division. How could a cell replicate single-stranded DNA so the daughter cells could
receive an exact copy of the genes present in the original cell?

Use your answer to explain why it is an advantage for DNA to have a double helix structure with
paired nucleotides.


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