6Pyrimidine Structures LOOKS like a “Pie” /single circle/ smallBoth Have “y” in name (Cytosine/Thymine)
7DNA Extraction using Wheat Germ Basic procedure: Lyse (bust) wheat germ cellsRupture cell walls, membranes and nuclear membrane to release DNA
8Materials for DNA extraction: Raw Wheat GermWarm water bath (50°- 60°C)Ethyl Alcohol (cold)Liquid detergent (Woolite, Dawn, Palmoliv)2 50 ml beakers1 Graduated cylinder (large)Glass stirring rod/ wooden stick/spaghettipaper towelsThermometer and Hot plate
9Obtaining a Wheat Germ Solution Prior to beginning the extraction, turn on hot plate and prepare the warm water (50°- 60°C).The heat softens cell membranes and the nucleus & inactivates enzymes that would cut the DNA into pieces
10How detergent Works:Detergent cleans dishes by removing fats & proteins.Soap molecules & grease molecules made of two parts :Head (likes water)Tails (hates water)When soap comes close to grease, it captures it,forming greasy soapy ball.
11Release DNA from Wheat CELLS …. The detergent removes the cell membranes and releases the DNA into the solution
12Precipitate the DNA Clouds of white strands are the DNA. The DNA is not soluble in ethyl alcohol, so it precipitates out (becomes solid and drops out of the solution) where the 2 liquids meet.Soap bubbles from the solutions will get trapped in the DNA strands.
13COLLECT THE DNAObserve the cloudy layer. This is the DNA. Place a clean glass stirring rod in the beaker with the DNA. Collect the DNA by winding it on the rod, and turning the rod in one direction.
15“See your DNA = Cheek the Code of Life” Cheek Cell DNA or“Cheek to Cheek”or“See your DNA = Cheek the Code of Life”
16“Spit Happens” DNA extraction of Cheek Cells Basic procedure:Lyse the cells rupturing the cell membranes and nuclear membrane to release DNAUse Gatorade: swish swish swishSpit, spit, spit
17RELEASE DNA FROM THE CELLS Add detergent to break open cell membrane to release DNA
18Precipitate the DNA Add ethyl alcohol to solution of “spit” What happens at the interface between the ethyl alcohol and the "DNA/spit" solution?
19DNA floats to surface(bubbles with tiny hair like white strings)
20COLLECT THE DNADNA is collected by winding it on the wooden stick or piece of spaghetti, and turning the rod in one direction.
21What do you think he sees? DNA on slideUse cover slip.Use diaphragm: to adjust the amount of light
22Why use Enzymes in some DNA EXTRACTIONS? Enzymes speed up chemical reactions.Meat Tenderizer has the enzyme PAPAIN.Used to cut proteins away from the DNA.Also, helps break down DNAase(enzyme that breaks down DNA)
23Why is it important to isolate the DNA of any organism? BiodiversityMedical curesMedical advancementOrganisms live in different environmentsSurvival of endangered species(reproduction)Blending of DNA (plants..genetic engineering)Making Healthy Smoothies.