Name______Hour______PCR Virtual Lab Answer the following questions as you complete this lab.

1. How many base pairs is the human genome made up of? ______

2. What does “PCR” stand for?______

3. What is this biotechnology used for (besides making copies of DNA)? ______

4. Is a lot of DNA required for a PCR reaction? _____ What does this mean about the size of the sample that you need to extract DNA from? ______

5. Why is a PCR test tube special compared to regular test tubes? ______6. What are primers and how many were added to the PCR tube? ______7. What are nucleotides and why were they added to the PCR tube? ______8. What is DNA polymerase and what does it do? ______

9. What is the PCR machine called, and what does it do? ______

10. Describe what happens to the DNA during cycle #1 at these specific temperatures: 950C - 500C - 720C - 11. How do you eventually end up with over a billion copies of your targeted DNA? ______Gel Electrophoresis Introduction

When you have enough copies of your targeted DNA through PCR, you are now ready to run Gel Electrophoresis. Scientists use this technique to sort DNA fragments into different lengths. Go here to answer the following question.

1. Gel electrophoresis sorts DNA strands by length because longer DNA strands travel through the gel slower than shorter strands. Why do scientists need to sort DNA strands by length? ______Name______Hour______Gel Electrophoresis Lab

Now that you have a good understanding of why we use this process, go here to complete a virtual Gel electrophoresis and answer the following question.

1. Where are the DNA samples inserted into the gel? ______

2. How do scientists make the DNA move once it is in the gel? ______

3. Which DNA strands move the farthest away from the starting point? ______

4. Why do we stain the DNA? ______

5. Why do we need to add the salt-solution buffer to the gel? ______

6. Why do we run a DNA size standard along with our sample? ______

7. Why should we not allow the stain ethidium bromide to touch our skin? ______

5. Real World Genetics You’re a surfer and a microbiologist. You want to find out if the near-by sewage treatment plant is contaminating your favorite beach with harmful bacteria species, so you collected a water sample while you were paddling out to catch some sick waves one day. Write a brief paragraph outlining how you would use genetic analysis to figure out whether the bacteria in question are in your sample. Name______Hour______