Name ___________________________
Objectives:
You will examine the four different nucleotides making up a DNA molecule and produce and replicate DNA by following the proper steps.
Materials:
 Cut outs of basic subunits of DNA
 Colored Pencils
 Scissors
 Tape or glue
Procedure:
1.
Color code the nitrogenous bases, phosphates, and sugars according to the following key:
2.
Cut out all of the units needed to make the nucleotides from the handout provided (YOU WILL BE
MAKING ONE MODEL WITH A PARTNER).
3.
Using the small squares and stars as guides, line up the bases, phosphates, and sugars.
4.
Glue or tape the appropriate parts together forming nucleotides.
5.
Construct a DNA model using the following sequence to form a row from top to bottom:
Thymine, Cytosine, Adenine, Guanine
6.
Let this arrangement represent the left half of your DNA molecule.
7.
Complete the right side of the ladder by adding the complementary bases. You will have to turn them upside down to make them fit.
8.
Your finished model should look like a ladder.
9.
To show replication, separate the left side from the right side, leaving a space of about 6-8 inches.
10.
Use the remaining nucleotides to complete the molecule using the left side as the template.
11.
Build a second DNA molecule by adding new molecules to the right half of the original piece of the molecule.
12.
Glue/tape the nucleotides together to form 2 complete DNA ladders. Glue/tape the ladders to a sheet of construction paper.
Results:
1.
Of the 4 bases, which other base does adenine most closely resemble? ________________________
2.
List the 4 different nucleotides: ______________________________________________________
3.
Which 2 molecules of a nucleotide form the sides of a DNA ladder? _________________________
4.
If 30% of a DNA molecule is Adenine, what percent is Cytosine? ____________________________
5.
What does the term replication mean? _________________________________________________