Expert answer:In this experiment, you will model the effects of

Solved by a verified expert:Experiment 1: Coding
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:

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:

_ _ _

_ _ _

_ _ _

_ _ _

_ _ _

_ _ _

M:

O:

S:

T:

U:

_ _ _

_ _ _

_ _ _

_ _ _

_ _ _

Create codons for:

Start:

Stop:

Space:

_ _ _

_ _ _

_ _ _

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

How many beads did you use?

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.

What does the sentence say now? (re-write the
entire sentence)

Mutations are simply changes in the
sequence of nucleotides. There are three ways this occurs:

Change a nucleotide(s)
Remove a nucleotide(s)
Add a nucleotide(s)

Using the sentence from exercise 21B:

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?

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 it doesn’t make
sense as a sentence, are there any words that do? If so, what words still
make sense?

Replace the 20th bead and add one
between bead numbers 50 and 51. What does the sentence say now? Does the
sentence still make sense?

In 3.a (above) you mutated one letter. What role do
you think the redundancy of the genetic code plays in this type of
change?

Based on your observations, why do you suppose the
mutations we made in 3.b and 3.c are called frame shift mutations?

Which mutations do you suspect have the greatest
consequence? Why?