HAPPY TUESDAY

Bellwork: 1. Collect Lab Materials (Goggles and Aprons)

2. Turn in HW - Page 43 (Franklin, Watson, & Crick)

3. If you were absent Friday, please turn in “Make-Up Work”.

4. QUICKWRITE – 50 word quickwrite explaining what Watson,

Crick, and Franklin discovered. Also, describe the following

picture and its relevance.

Unit 3 – DNA & ReplicationAll Parts Due TOMORROW (10/21/15)

1. DNA2. Nucleotide3. Nucleic Acid4. Deoxyribose5. Nitrogenous Base6. Hydrogen Bond7. Adenine8. Cytosine9. Guanine10.Thymine

11.Purine12.Pyrimidine13.Double Helix 14.Antiparallel15.Semi-Conservative16.DNA Polymerase17.Helicase18.DNA Replication19.Complementary Strand

Pg 39

Essential Question Where can we find

DNA?Standard

B.6A – Identify components of DNA, and describe how information for specifying the traits of an organism is carried in

the DNA

PG 44

Procedure1. Obtain a small cup of Salt Water. Swish the Salt Water around in your mouth

for 1 to 2 full minutes. As you swish, gently and continuously scrape the sides of your cheeks with your teeth to help release your cheek cells.

2. Spit the Salt Water (with your cheek cells) into a test tube. Dispose of the cup.

3. Hold the test tube at an angle and add one pipette full of cell lysis solution to your cheek cell solution.

4. Cap your test tube with your thumb and invert it 5 times to mix the two solutions.

5. Allow the mixture to sit for 15 minutes.

6. Work on the Page 44 while you wait.

Page 44: DNA Extraction Lab Questions*Write the question and answer in complete sentences*

1. What is the purpose of DNA?

2. What did the DNA look like? Relate what you know about the chemical structure of DNA to what you

observed today.

3. A banana is composed of eukaryotic cells. Where is its DNA located?

4. Where is the DNA located in a prokaryotic cell? Why?

5. What is the monomer of DNA?

6. What is this monomer composed of?

7. How does the genetic code (DNA) differ from organism to organism?

8. Why is it important for scientists to be able to remove DNA from an organism? List two reasons.

Procedure cont’d7. After 10 minutes, hold your test tube at an angle, add ethyl alcohol to

your test tube (Add one pipette full of alcohol to the test tube) by letting it run gently down the side of the test tube. You should have two distinct layers. Do not mix the cheek cell solution with the alcohol!!!

8. Watch as cobweb-like strands of DNA begin to clump together where the alcohol layer meets the cheek cell solution.

9. Use a plastic pipette (the same one used for the ethyl alcohol) to transfer your DNA into a centrifuge tube. To do so, place the pipet near the DNA and draw the DNA and some alcohol into the pipet.

10. Continue working on Page 44 If you do not finish in class, it is homework. It will be due TOMORROW when you get to class.

Page 44: DNA Extraction Lab Questions*Write the question and answer in complete sentences*

1. What is the purpose of DNA?

2. What did the DNA look like? Relate what you know about the chemical structure of DNA to what you

observed today.

3. A banana is composed of eukaryotic cells. Where is its DNA located?

4. Where is the DNA located in a prokaryotic cell? Why?

5. What is the monomer of DNA?

6. What is this monomer composed of?

7. How does the genetic code (DNA) differ from organism to organism?

8. Why is it important for scientists to be able to remove DNA from an organism? List two reasons.