Farm Tech Days DNA Glop

Intro to Two "Exploration Stations" in Genetics: Manduca (follow link) and DNA Glop from Wheat Germ (see below)
These two Exploration Stations give learners experience in two different approaches to studying genes, or the study of genetics.	Back to Tech '04 Home page
One is the direct approach of studying DNA. This is the "Extracting DNA Glop from Wheat Germ" Exploration Station.
The other is the more classical approach (since Mendel in the 1860's) of studying the patterns of inheritance of traits from generation to generation to generation. This is the Manduca Exploration Station.
Extracting DNA Glop from Wheat Germ The Grist: Is DNA something you can actually see, work with, handle, and pull out from ordinary living things, including foods such as wheat germ? The Gist of the Grist: Given the choice between having a plate full of cookies and the recipe card for cookies, which would you take, and why? If you have cookies, can you eat them right away? Do you avoid having to go through the work of making them? But once they're gone, can you make more? If you have the recipe, what do you have? Ingredients? Oh? Is there a pile of flour on the recipe card? So do you have ingredients, or do you have information about the ingredients? Is it a powerful thing to be able to store, retrieve, edit, copy and share recorded information, whether it's a recipe, a DVD, or DNA?		Click image to see larger Click here to download 4 x 5 foot poster image
So why do we study DNA? Because DNA is like the genetic recipe card for living things: it's the stuff that carries the information. Some key "In" words Information Ingredients Insight The Activity:
Please take a big tube with the red cap and locate the 20 mark. The mark indicated 20 what? About how big is 1 mL?	Remove the cap, add water to the tube until it reaches the 20 mark, then put the cap back on tightly, and shake vigorously until wheat germ and water are appropriately goopy.
Next take one green tube. Can you guess what the green goo is? What is the purpose of adding it to the water and wheat germ mixture?	Add the green goo and then gently rock the tube (think of waving with the tube in your hand) until all the soap is dissolved.
Carefully add alcohol up to the 35mL line. Why does the alcohol stay separate from the water?	The whitish silken threads that are floating up out of the water make up the DNA glop from the wheat germ.
The Activity: Please take a big tube with the red cap and some raw wheat germ. Please read the destruction sheet, and look at the four photos across the top. What part of the wheat do we eat? Do we eat the roots, the stems, the leaves, or the flowers? Or do we eat the seed? If you slice the seed real thin and look at it under a microscope, what do you see? If you look in the cells what is the big round thing you may see? If you look in the nucleus you may see chromosomes, and what are chromosomes made up of? The recipe is for extracting DNA glop from wheat germ.
		What does extract mean? Does that mean we're going to make DNA?…or does it mean we're gonna pull DNA out? When you go to the dentist and the dentist extracts a tooth, has the dentist made a new tooth or has the dentist merely pulled out an existing tooth? What other words besides "extract" have that "tract" root word? Four minus two = subtract Lawyers help make them = contract Insults do this = detract Ice cuts its = traction Farmers use them = tractors Also: retract
First puzzle: find the 20 mark on the side of the tube. Second puzzle: figure out how you can fill the tube with water up to the 20 mark without going over While shaking for 2—3 minutes, you can go through the recipe/cookie parable if you didn't start with that. Otherwise, talk with the learners about their ideas of what DNA is. And encourage the people to read ahead on the instructions. Usually you can cut the shaking to 2 minutes. Then ask the people to "stop, pop the top, and smell the stuff. And put your finger in the stuff to feel how it feels. " Ask "What's next?" and give the people time to refer to the instructions. Find the small 1.5 ml plastic tubes with green Palmolive dishwashing liquid. Pop the top and set the tube on the rim of the big tube and let the green stuff drain into the tube for about 10 seconds. What can people do with the 1.5 ml soap tube? They can either take it home as a souvenir, or throw it away. Next, remind people — do the instructions say to shake vigorously or do they say shake gently, and don't make foam? Show them how to rock the tube over head like you're waving goodbye to someone who is far away. After about two minutes, again say "Stop, pop the top, and smell. Now put your finger in the goo? What's it feel like now?"
Next, remind people — do the instructions say to shake vigorously or do they say shake gently, and don't make foam? Show them how to rock the tube over head like you're waving goodbye to someone who is far away. After about two minutes, again say "Stop, pop the top, and smell. Now put your finger in the goo? What's it feel like now?" Next, show people how to pour the blue—dyed alcohol into the tube; "Do you keep the tube straight up and down, or do you hold the tube almost flat, like that?" "Next, pour the alcohol in Slow Ly so it floats on top, rather than mixing in; and pour til it gets to the 35 mark on the side of the tube" Show them how to use a wooden Q–tip to gently swirl the fine white threads in the blue; encourage them to "Stay up in the blue, don't go down in the goo" with their wooden sticks. They can wind the DNA glop around the wood stick and then transfer the glop to a clean white 1.5 ml plastic tube, and they can take the tube home as a souvenir. The glop is only partly DNA; it also contains protein and carbohydrates. The key thing: is DNA something so small you can't work with it? Or is something that you can collect enough to be able to see? Why study DNA? Because DNA is like the genetic recipe card for life. And if you had the choice between having a plate full of cookies and the recipe card for cookies, which would you take?

Intro to Two "Exploration Stations" in Genetics: