Decoding the Code
How does DNA determine the traits of organisms?
Introduction: In this activity you will examine the DNA sequence of a fictitious organism, the Snorks.
Snorks were discovered on the planet Dee Enae in a distant solar system. Snorks only have one
chromosome with eight genes on it. Your job is to: 1.) analyze, transcribe, and translate the genes, 2.)
determine what traits the organism has, and 3.) create/draw organisms with the appropriate traits.
Amino Acid Sequence
20-11-13
20-12-13
20-16-16
13-14-15
16-2-5
16-4-5
12-7-8
5-7-8
9-8-8
9-4-8
11-3-2
11-3-3
6-6-10
6-6-14
1-2-3
4-5-6
Trait
Hairless
Hairy
Plump
Skinny
4-legged
2-legged
Round head
Block head
Short
Tall
Small eyes
Large eyes
Male
Female
Green
Purple
tRNA triplet
CCC
CGA
CGC
AAC
GGG
AUC
AGG
AAA
UUU
CUA
GGA
GGU
UAU
AAG
GGC
AGC
ACC
Amino Acid Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
20
Procedure
You are given the chromosome (with 8 sequenced genes) from four (4) different Snorks. Each gene has
only three (3) amino acids (A.A.). Your job is to determine the sequence of amino acids for each
specimen. Write the complementary mRNA, the connecting tRNA, the amino acid for which it codes, and
the corresponding trait in the chart below.
Snicker Snork
DNA
mRNA
tRNA
A.A.
Trait
ACCGGATAT/CCCCGACGC/TATAAGGGC/AGCCGAGGG/GGTAGGAAA/TTTAAAAAA/GGACGCCGA/ATCATCAAG
UGGCCUAUA/
ACCGGAUAU/
20-11-13/
Hairless/
Snuffle Snork
DNA
mRNA
tRNA
A.A.
Trait
ACCGGATAT/AACGGGATC/TATAAGGGC/AGCAACGGG/GGTAGGAAA/TTTAACAAA/GGACGCCGA/ATCATCCTA
Snapple Snork
DNA
mRNA
tRNA
A.A.
Trait
ACCGGTTAT/ CCCCGACGC/ACCAGCAGC/ AGCCGAGGG/GGGAGGAAA/TTTAAAAAA/GGACGCCGC/ATCATCAAG
Snooper Snork
DNA
mRNA
tRNA
A.A.
Trait
ACCGGTTAT/ AACGGGATC/ ACCAGCAGC/ AGCAACGGG/GGGAGGAAA/TTTAACAAA/GGACGCCGC/ATCATCCTA