Download DNA Replication Computer Gizmo

Gizmo: Ch 12.2 & 12.3 Building DNA Name _____________________________
https://www.explorelearning.com/
Prior Knowledge Questions (Do these BEFORE using the Gizmo.)
1. Deoxyribonucleic Acid stands for _________________________
2. DNA is found in the cell’s ______________________________________
3. Building block’s (or monomers) of DNA are ____________________________
4. DRAW and LABEL the 3 molecules that make up one DNA nucleotide:
5. Define double helix - _______________________________________________
_________________________________________________________________
6. (TRUE or FALSE) The two strands of DNA are considered antiparallel and
oriented in opposite directions.
7. (TRUE or FALSE) DNA is a type of nucleic acid.
DNA is an incredible molecule that forms the basis of life on Earth. DNA
molecules contain instructions for building every living organism on Earth, from
tiny bacteria to massive blue whales. DNA also has the ability to replicate, or make
copies of itself. This allows living things to grow and reproduce. In the previous
chapter, you learned that before cells divide, they must first copy the DNA in order
to maintain chromosome number.
Warm-Up
The Building DNA Gizmo™ allows you to construct a DNA
molecule and go through the process of DNA replication
and examine the components that make up a DNA
molecule.
8. What are the two DNA components shown in the Gizmo?
_______________________________ and ______________________________
9. A nucleoside has 2 parts: a pentagonal sugar (deoxyribose) and a nitrogen base
(in color). When a nucleoside is joined to a phosphate, it is called a nucleotide.
How many different nitrogen bases do you see? ________________
Note: The names of these nitrogenous bases are adenine (red), cytosine (yellow),
guanine (blue), and thymine (green).
Activity A:
Build DNA
Get the Gizmo ready:
 Click Reset
10. Follow the steps given in the Gizmo to construct a molecule of DNA.
Stop when the hint reads: “The DNA molecule is complete.” In the spaces
below, list the sequence of nitrogen bases on the left-hand side of the original
DNA molecule and the right-hand side.
“Original DNA Molecule”
Left Side
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Right Side
11. What 2 molecules make up the backbone (or sides) of the DNA molecule?
_____________________________ and _______________________________
12. What molecules make up the rungs (or middle) of the DNA molecule?
___________________________________
13. In DNA, adenine always joins to ___________________________
14. In DNA, cytosine always joins to ___________________________
15. The left side of a DNA molecule is shown. Draw the complementary right side.
Activity B:
DNA
Replication
Get the Gizmo ready:
 Make sure the hint reads: “The DNA
molecule is complete.”
16. An enzyme is a protein that facilitates certain cell processes. Click release
enzyme to release DNA helicase. What does this enzyme do to the DNA?
________________________________________________________________
17. Click release enzyme to release DNA polymerase. Drag one of the nucleotides
to a corresponding nitrogen base on one of the two strands. What is the role of
DNA polymerase in this process?
________________________________________________________________
18. Complete the two molecules of DNA by dragging all of the nucleotides to their
corresponding locations. Compare the two completed DNA molecules. What
do you notice about the two molecules?
________________________________________________________________
19. Compare the two daughter DNA molecules to the original DNA (refer to #10).
What do you notice about the molecules? SAME or DIFFERENT
_______________________________________________________________
20. Why is DNA replication such an important process?
________________________________________________________________
21. Where in the cell does DNA replication occur?
___________________________