Download Name

Name_________________________
Date__________
DNA Construction
Problem: What does a model of DNA look like?
Materials:
Tracing Paper
Scissors
String
Meter Stick
Construction Paper
Markers, crayons or colored pencils
Tape or glue
Heavy colored blank paper
Procedure:
1.) Trace the figures for the Deoxyribose sugar and the Phosphate group onto tracing paper. Out of
construction paper, cut out 24 Deoxyribose figures and 24 Phosphate figures. Use one color for the
Deoxyribose figures and another color for the Phosphate figures. Label them with an “S” for
Deoxyribose sugar and a “P” for Phosphate group on both sides of the figures.
P
S
2.) Trace the four nitrogen bases shown below with tracing paper.
A
A
C
T
G
Name ________________________________________________
3.) Cut out the four tracings and copy each part onto heavy paper to make
Use: Yellow for “T”- Thymine
Green for “G”- Guanine
6 copies of each
Pink for “A”- Adenine
Blue for “C” - Cytosine
4.) Label each nitrogen base with the correct letter (A,T,G,C). Label on both sides of the figure.
5.) Measure and cut out two 2 meter lengths of string. Tape down one length of the string at both ends
onto your work area.
6.) Start from the end of the taped down string, place a Sugar, then a Phosphate, alternating with the
sugars and phosphates, and then tape the 12 Sugars and 12 Phosphates on each string. For the other
string, start with a Phosphate and end with a sugar.
7.) To each Sugar on one strand, tape a nitrogen base.
8.) To the other strand, arrange the remaining nitrogen bases according to how they will pair following
the rules of nitrogen base pairing. Tape them in the proper order to the Sugar and then tape or glue
them to the corresponding nitrogen base on the other strand of your DNA model.
*** If you were not careful about how you distanced your pieces or taped them, they will not
line up properly. If this is you, fix it!! We do not want any mutant DNA strands.
Data and Observations:
1.) To the lines marked left and right strand, record the order of the bases on your DNA model?
Left strand-- Right strand
mRNA
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
____--____
_____
Amino Acid
___________________
___________________
___________________
___________________
2.) How is your DNA model (above) different from those of your classmates? Be specific please.
3.) In what ways is your entire DNA model similar to your classmates’ models? Again, be specific.
Analysis:
1.) Where would you find this model if it were in a eukaryotic cell? ___________________________________
2.) Should your model under DNA replication:
a.) How many molecules of DNA will be produced ___________________________________
b.) What will the strands of DNA look like? __________________________________________
__________________________________________________________________________________________
3.) Why did strings make your DNA model a more realistic model? Look at an image of DNA to help you out.
4.)
5.)
Now to your strand on the previous page, transcribe the right strand of DNA to make mRNA.
Remember the base pairing rules and that Uracil takes the place of Thymine.
Using the Genetic code wheel below, translate your DNA’s message by filling in the amino acids on the
previous page.