In this experiment, you will model the effects of mutations on the genetic code. Some mutations cause no structural or functional change to proteins while others can have devastating affects on an organism.
Materials
Red Beads
Blue Beads Yellow Beads
Green Beads
Procedure:
1. Using the red, blue, yellow and green beads, devise and lay out a three color code for each of the following letters (codon). For example Z = green : red : green.
In the spaces below the letter, record your “code”.
C:
E:
H:
I:
K:
L: red green red blue yellow blue red blue red green yellow green red green blue yellow green blue
M:
O:
S:
T:
U: blue yellow green blue green green green red green red blue yellow yellow green yellow
Create codons for:
Start:
Stop:
Space:
red yellow red blue red blue red green yellow
2. Using this code, align the beads corresponding to the appropriate letter to write the following sentence (don’t forget start, space and stop): The mouse likes most cheese
a. How many beads did you use? 87 beads
There are multiple ways your cells can read a sequence of DNA and build slightly different proteins from the same strand. We will not go through the process here, but as an illustration of this “alternate splicing”, remove codons (beads) 52 - 66 from your sentence above.
b. What does the sentence say now? (re-write the entire sentence)
The mouse likes cheese
Mutations are simply changes in the sequence of nucleotides. There are three ways this occurs:
1. Change a nucleotide(s)
2. Remove a nucleotide(s)
3. Add a nucleotide(s)
3. Using the sentence from exercise 1B:
a. Change the 24th bead to a different color. What does the sentence say now (re-read the entire sentence)? Does the sentence still make sense?
The molse likes cheese. No, the sentence does not make sense.
b. Replace the 24th bead and remove the 20th bead (remember what was there). What does the sentence say (re-read the entire sentence)? Does the sentence still make sense? If