DNA to Hairy toes, the journey of proteins…

How do the traits on a chromosome determine the characteristics of an organism?

• Colored pencils
• White drawing paper

You have been asked to predict the physical appearance of the alien organism CHNOPS. The only information known is that the species has 1 chromosome. A CHNOPS chromosome is made up of six genes (A, B, C, D, E, and F), each of which is responsible for a certain trait.

What to do:

1. To determine the trait for Gene A of your CHNOPS, fill in the information in the box labeled Gene A in the Data Table. Notice the sequence of nucleotides (codons) in DNA. On the line provided, write the codon sequence of mRNA that is complementary to DNA. Then, on the line provided, write the sequence of nucleotides (anticodon) of tRNA that are complementary to mRNA. See Data Table-Gene A for example. 

2. In order to determine the sequence of amino acids, match each tRNA triplet with the specific with the specific amino acid in Figure 1. Using a - (hyphen) to separate each amino acid number, record this information in the appropriate place in the Data Table. See Data Table-Gene A for example.

3. Using Figure 2, find the trait that matches the amino acid sequence. Record this information in the appropriate place in the Data Table. See Data Table-Gene A for example.

4. Repeat steps 1-3 for the remaining genes (B through F).

****(There should be 4 Columns under each of the bold and underlined below. The information under the columns is not in its proper spacing because of the formatting of Claris Home Page, however the information is separated in four different areas. These breaks correspond with each column.)******

tRNA Anticodon Amino Acid Number Amino Acid Sequence Trait

ACC 20 20-11-13 Hairless

AGC 16 20-12-13 Hairy

CGA 2 20-21-21 Plump

AAC 4 13-14-15 Skinny

CGC 3 16-2 Four-legged

GGG 5 12-7-8-1 Long nose

AGG 7 5-7-8-1 Short nose

AAA 8 9-8 No freckles

UUU 9 9-4 Freckles

GGU 12 11-3-2 Blue skin

UAU 13 11-3-3 Orange skin

CCC 1 6-6-10 Male

AUC 6 6-6-14 Female

CUA 10

GGA 11

Figure 1 (first two columns above) Figure 2 (last two columns above)

Data Table

Observations: Complete the table following the steps above.

****(There should be 3 Columns under each of the bold and underlined below. GENE A / GENE B / and GENE C. (Notice the different colors for each column) The information under the columns is not in its proper spacing because of the formatting of Claris Home Page, however the information is separated in four different areas. These breaks correspond with each column.)******

Gene A Gene B Gene C

DNA: ACC GGT TAT DNA: AGC CGA DNA: TTT AAC

mRNA: UGG CCA AUA mRNA: mRNA:

tRNA: ACC GGU UAU tRNA: tRNA:

Amino Acid

Sequence: 20-12-13 Amino Acid

Sequence: Amino Acid

Sequence:

Trait: Hairy Trait: Trait:

Gene D Gene E Gene F

DNA: GGA CGC CGA DNA: GGG AGG AAA CCC DNA: ATC ATC CTA

mRNA: mRNA: mRNA:

tRNA: tRNA: tRNA:

Amino Acid

Sequence: Amino Acid

Sequence: Amino Acid

Sequence:

Trait: Trait: Trait:

Analysis and Conclusions:

1. Distinguish between translation and transcription:

2. Where does transcription occur in the cell?

3. When does transcription occur?

4. Where does translation occur in the cell?

5. When does translation occur?

6. What is the relationship between the codon and the anticodon? Describe the job they perform together.

Critical Thinking:

7. Suppose you know the makeup of specific proteins in a cell. How would you determine the particular DNA code that determined the proteins? Be sure to describe the process you would use in a step by step fashion.

8. How could one change in a DNA nucleotide alter the formation of the translated protein?

Give an example.

Challenge:

Create two additional traits for your CHNOPs and give their initial DNA sequence, mRNA codon, and tRNA anticodon. Include the resulting amino acid sequence.

Draw the organism you've determined. Be sure to make all of the characteristics visible.

Brain Challenge: What do you think each letter in the word, CHNOPs, stands represents?

(Hint: It's ELEMENTary:).