Your Challenge: You will isolate the DNA from a sample of spinach.
What You Need:
A blender (or something to squish the spinach with)
Spinach (about ½ cup)
Dish Washing Soap (about 2 tablespoons)
Meat Tenderizer (just a pinch)
Cold water (about a cup)
Salt (about ¼ teaspoon)
1. Blend the spinach, salt, and water together in a blender until the mixture looks soupy.
2. Pour this mixture through a strainer and into a measuring cup.
3. Add the dishwashing soap, and wait 10 minutes.
4. Add the meat tenderizer to the mixture.
5. Add the rubbing alcohol (add the exact volume that is already in your measuring cup).
6. Wait 3 minutes. Are any changes occurring?
7. Look into the cup for a white-cobweb type substance. That is the DNA.
How does this work? First the cells are broken up in the blender. Next the detergent is added to emulsify (or break up) fat. The meat tenderizer is added to break down the proteins in the spinach. DNA is soluble in water but not alcohol. This last step allows the DNA to precipitate out so we can collect it.
- If you were to stretch out the DNA from those 46 chromosomes in one cell and lay it end to end, it would be over 2 yards in length.
- It takes about eight hours for one of your cells to completely copy its DNA.
- If the total DNA in one person were laid in a straight line, it would stretch to the sun and back over 30 times (it’s 93 million miles from here to the sun).
- You could fit one million threads of DNA across the period at the end of this sentence.
- Humans are 99.9% genetically identical – only 0.1% of our genetic make-up differs.
- Our genes are remarkably similar to those of other life forms. For example, we share 98% of our genes with chimpanzees, 90% with mice, and 85% with zebra fish!
- Less than 2% of the total DNA carries instructions to make proteins. The rest is called ‘junk’ DNA, because it is a hodge-podge of sequences that does not seem to code for anything.