Double Helix DNA Model
With over 100,000 different proteins to manufacture, how the heck does
our body get it right? When one thinks of the amount of
information the body needs to keep track of, - eye, hair and skin color,
protein sequence, toenail size, etc. - it would seem a task for a
supercomputer to record all of the necessary information. In
essence it is. But not a supercomputer made of silicon wafers and
TV screens, rather one made of an intricate biomolecule called DNA.
In our model we use a white ball to represent sugar and a red ball to represent phosphate.
What is impressive about DNA is that each sugar molecule in the strand also binds to one of four different nucleotide bases. These bases: Adenine (A), Guanine (G), Cytosine (C) and Thymine (T), are the beginnings of what we will soon see is a molecular alphabet. Each sugar molecule in the DNA strand will bind to one nucleotide base. Thus, as our description of DNA unfolds, we see that a single strand of the molecule looks more like this:
In our model we use light blue balls for Cytosine, light green balls for Guanine, yellow balls for Adenine and Orange balls for Thymine.
Each strand of DNA contains millions or
even billions (in the case of human DNA) of nucleotide bases.
These bases are arranged in a specific order according to our genetic
ancestry. The order of these base units makes up the code for
specific characteristics in the body, such as eye color or nose-hair
length. Just as we use 26 letters in various sequences to code for
the words you are now reading, our body's DNA uses 4 letters (the 4
nucleotide bases) to code for millions of different characteristics.
How to make the model?
Paint all the balls with water based or latex color. Following are the colors that we used in our model.
The number of different color balls in our model is as follows:
If you want to separate your DNA model from the base, you will need to use a small amount of wood glue on the ends of toothpicks. If you do this, you can later remove the strings that you used to tie some of the pairs to the column and your DNA model will be removable. For more strength, you may use a very thin wire or string to connect the center of pairs together. If you do this, tie the string to the center of ladder every few steps and make sure that the string is well stretched.