Deoxyribonucleic acid, or DNA, is found in the cell of every living organism. It is often called the "blueprint" of life. It has a double-helix structure that contains genetic information. The rungs of this twisted ladder are composed of four bases: Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). Hydrogen bonds hold these bases together. A misplaced base in the structure is called a mutation.
To get an up close visual of what a strand of DNA looks like, you will need colored beads or small colored Styrofoam balls. If you use the beads, you will need some nylon or thread to string them together. You can use glue and toothpicks to attach the Syrofoam balls to each other. Use white for deoxyribose and purple for the phosphate substrate. Assign a color for each base. Then, start making nucleotides or joint molecules by adding your base pairs to the deoxyribose and phosphate substrate. While building your model, remember that A is paired with T, C is paired with G, both in equal amounts.
You will need three empty glasses. Fill one glass with one-quarter cup of alcohol and chill it. Next, take the other glass, fill it halfway with tap water and then add two teaspoons of salt. Mix the saline solution in your glass with two teaspoons of detergent until the salt has dissolved completely. Next, get a small, peeled banana and mash it in a bowl or a small plastic bag. Take five teaspoons of the detergent-salt solution and mix it with the banana until the result has a frothy texture. After stirring for about 30 seconds, get another glass, put a coffee filter on top of it and adhere it to the glass with a rubber band. Pour the banana mixture on top of the filter and let it seep through the filter for at least 10 minutes. Now pour the liquid you harvested into the chilled glass of alcohol. If you wait for a few minutes, you will observe white clusters in the chilled alcohol. This is the DNA of the banana.
If you don't have any bananas handy, you can also extract DNA from broccoli. You will need to put a half cup of broccoli, one cup water and one-eighth teaspoon of salt in a blender. With your blender set on high, blend your ingredients for 15 seconds. Now get a strainer and strain the liquid from the mixture. Mix 30 milliliters of liquid detergent to the broccoli liquid. Wait 10 minutes and pour the mixture in smaller glass containers. Add a touch of pineapple juice to add enzymes. Then take a bottle of ethyl alcohol and start pouring slowly on the inside part of the glass, so that the alcohol will have its own layer on top of the broccoli soup. Observe for a few minutes, and when you spot the wet paper substance that forms in the mixture, you have successfully separated some broccoli DNA.
DNA controls inherited traits. Augustinian Monk Gregor Mendel discovered the basic laws of inheritance by observing pea plants. You can do the same. Get some pea seeds. Make sure some pea seeds are wrinkled, while others are smooth. Plant the seeds in pots and label each pot, wrinkled or smooth. When the peas have sprouted and turn into pea plants, place a smooth pea plant next to a wrinkled pea plant in a sunny place. Next place two smooth pea plants near each other and two wrinkled pea plants near each other in sunny locations. Make sure each set of plants is not located near another set of plants. As the pea plants grow, they will pollinate each other. Harvest your peas from each set of plants and record the results. You should see that the two smooth pea plants produced mostly smooth peas and the wrinkled peas produces mostly wrinkled peas, but the smooth and wrinkled plant produced both smooth and wrinkled peas.