Name ______________________________ Date ___________________ Blk____
DNA Replication K’NEX Activity
You will be using K’NEX to build a DNA model and then demonstrate how
DNA replicates. There is an instruction guide that shows you pictures for
each step and explains how to assemble the pieces, but it does not explain
what is actually happening to the DNA inside your cells.
1. The first step is to assemble the pieces of the DNA molecule. DNA is a
nucleic acid that is made up of individual units called _____________.
There are four of these subunits: adenine, cytosine, guanine, and
thymine. They are made of three parts: a nitrogenous base,
____________________, and _____________________.
Look on page three. You will be assembling these subunits. You need to
make 7 thymine units, 7 adenine units, 5 cytosine units, and 5 guanine
units. You also need 7 double H bonds (red/orange) and 5 triple H bonds
(black). Draw a picture of the one of the units you assemble, and label
the three parts of these units on both pictures.
2. Turn to page 4. The diagram shows you how to assemble the DNA
molecule. Notice that certain units always pair with other units.
Adenine always pairs with ________________________.
Cytosine always pairs with ________________________.
Name ______________________________ Date ___________________ Blk____
3. Now that your DNA molecule is assembled, describe what you see. Make
sure to include the shape and any color patterns.___________________
__________________________________________________________
__________________________________________________________
__________________________________________________________.
4. Turn to page 6. You will now transform your DNA model into a double
helix. Follow the directions on the page. Why is the double helix shape of
DNA important? _____________________________________________
__________________________________________________________
__________________________________________________________
__________________________________________________________
__________________________________________________________.
5. Turn to page 10. You will now unwind your DNA molecule and begin the
process of DNA replication where an exact copy of your original strand
will be made. First, you need to create more nucleotides using the guide
on the bottom of page 11. Notice that the deoxyribose sugar is a different
color. In real life they are the same color, but you will use a different
color to show the difference between the original nucleotides and the new
nucleotides.
Step 1. Replication begins with a ______________________DNA
molecule. The molecule un-zips into _____ _____________________
strands. These strands are called the _____________________
strand and the _______________________ strand.
Step 2. When assembling the two new daughter strands, it is important
that you pay attention to the order of the _____________________
bases and remember that adenine always pairs with ______________
and guanine always pairs with _______________.
Name ______________________________ Date ___________________ Blk____
Step 3. You now have two molecules of DNA, each with a
______________ strand and a daughter strand. What do you notice
about the two
strands?_________________________________________________
________________________________________________________
________________________________________________________
_______________________________________________________.
Why is important that each DNA molecule have both a parent strand
and a daughter strand? ____________________________________
________________________________________________________
________________________________________________________
________________________________________________________
________________________________________________________
________________________________________________________
_______________________________________________________.