NAME:_____________________DATE:___________________PERIOD:_______
The Phenotype of the Wild Snork
During one of my recent excursions to the wilds of Schmidlandia, I discovered a
previously unknown creature. I have named this new life form Snorkus
schmiddicus, or “Snork” for short. I was able to capture four different
individuals and collect a sample of their DNA. They were then released
unharmed, but pretty angry.
Interestingly, the Snork species has only ten genes. Each gene is only three base
pairs long with no introns. I transcribed the DNA sequences of the four
individuals into RNA sequences, which appear below. In the Snork, all genes
create a protein that affects the Snork’s appearance. Your job is to analyze the
RNA sequences, determine the protein sequence it codes for and then
determine the traits of each Snork. Finally, you can sketch the phenotype of
each Snork.
Since it was night in Schmidlandia, I was unable to accurately describe the
phenotype of the Snork. Be creative as you can with their appearance!
Procedures:
1. Use the codon table in your book to determine the protein sequence of
each Snork gene. Write the protein sequence on your worksheet.
2. Use the attached protein table to determine the trait of each Snork. You
will have 10 traits for each Snork.
3. Using the ten traits, sketch EACH SNORK with its name on another sheet
of paper. You will have 4 Snorks in total.
4. Answer the questions.
1. Snicker Snork
AUG | GUC AGC AAA | UAC CCC GAA GAG AAA | CUC UUA AGU GCG | GCU GUU GUG |
CAU CAU | GUU UUU UAC | GAU AUC UUA CUG CCC ACC | GAC GAC GAU GCC | UUU UCU
GGG | AGA UAU UGU | UAA
Protein
Sequence
Traits
2. Snuffle Snork
AUG | GUA UCU AAA | GUU CCU ACU GAA AAG | CUU CUC CUC CCC | GUU GCG GCU | CAU
CAC | GUA UUU UAU | GAU AUU CUU CUG CCC ACA | GUU GAC GAC GCA | UUC UCG GGU
| AGA UAU UGU | UAA
Protein
Sequence
Traits
3. Snocker Snork
AUG | GUC AGC CUU | GUU CCC ACA GAA AAA | CUC UUA AGU GCG | GUU GCG GCU | CAC
AUU | UCU CCC GUA | GAU AUU CCC CCC CCC ACC | GAU GAC GAC GCA | UUC UUU GGG |
CGC CGG GAC | UAA
Protein
Sequence
Traits
4. Snoopy Snork
AUG | GUA UCC CUC | UAC CCC GAG GAA AAA | UUA UUA CUG CCC | GCU GUU
GUA | CAU AUU | UCU CCC GUA | GAU AUU CUU CUG CCC ACA | GUU GAU GAU
GCC | UUU UCU GGU | CGC CGU GAC | UAA
Protein
Sequence
Traits
Protein Table
Genes
Amino Acid (Protein) Sequence
Trait Description
Gene 1 - body covering
val - ser - leu
hairless
val - ser - lys
hairy
tyr - pro - glu - glu - lys
plump
val - pro - thr - glu - lys
skinny
leu - leu - leu - pro
3 legged
leu - leu - ser - ala
2 legged
ala - val - val
round head
val - ala - ala
square head
his - ile
tail
his - his
no tail
ser - pro - val
blue pigment (hair/skin)
val - phe - tyr
red pigment (hair/skin)
asp - ile - leu - leu - pro - thre
small eyes
asp - ile - pro - pro - pro - thre
large eyes
val - asp - asp - ala
circular mouth
asp - asp - asp - ala
rectangular mouth
phe - ser - gly
pointed standing-up ears
phe - phe - gly
rounded floppy ears
arg - tyr - cys - lys
long spaghetti like arms
arg - arg - asp - thre
short stumpy arms
Gene 2 - body style
Gene 3 - legs
Gene 4 - head shape
Gene 5 - tails
Gene 6 - body pigment
Gene 7 - eyes
Gene 8 - mouth
Gene 9 - ears
Gene 10 - arms
Questions:
1. How does DNA determine the traits of an organism?
2. Do all proteins affect the phenotype of an organism?
3. Look at Gene 10 for spaghetti-like arms. Describe what your Snork might look like if its
protein sequence was arg-tyr-arg-lysine instead of the correct sequence.
4. What would cause a protein to have the incorrect sequence?