DNA Deoxy…what? A guide to building a model. Objective: Our goal is to understand the structure and function of DNA molecules, including the rules of base pairing. We will do this by making scientifically accurate models of the DNA double helix.

What is DNA? DNA stands for “deoxyribonucleic acid” Like water (which is always made of 2 Hydrogen and 1 Oxygen), DNA is a molecule. This means that DNA is always made of the same things, it is just the order of those items that DNA provides the instructions for building and operating all living things. The DNA instructions are divided into segments called genes. makes us different!

Where is DNA?

Before We Begin… There are four types of chemical bases in DNA: Adenine (A), Cytosine (C), Guanine (G), and Thymine (T). They form pairs in very specific ways: Adenine (A) always pairs with Thymine (T) and Cytosine (C) always pairs with Guanine (G).

Interesting Fact Each cell in your body contains a lot of DNA. In fact, if you pulled the DNA from a single human cell and stretched it out, it would be three meters long! That’s about as long as a car. How does all that DNA fit into a cell? Chromosomes!!!

Nucleotide

Base Pairs

CG TA GC TA CG TA CG GC TA Group 1 Widows Peak Group 2 Bent Pinkie Group 3 Attached Ear Lobe TA CG AT Group 4 Non- Tongue Roller TA AT GC AT Group 5 Hitch Hiker’s Thumb TA AT CG Group 6 Thick Neck Group 7 Curly Hair TA GC TA CG Group 8 Dimples Deoxyribose: Red Phosphate: Blue A (Adenine): Green C (Cytosine): Yellow G (Guanine): Purple T (Thymine): Orange Each person is required to do 4 nucleotides Put your name on the ones you do! Put it together in the right order to create your gene TA GC AT GC

Directions Working in groups of 4 you will construct 4 different parts of the DNA molecule to form a double helix. Each group will work on completing a different sequence of DNA. Follow the directions on the sheet carefully and be sure to double check each other’s work. Remember, the base pairs must be combined correctly!