Biology
DNA and Protein Synthesis
DNA My Way
Name
Date
Period
Purpose
 To assemble a paper model
 To learn which nitrogenous bases bond with which
 To learn that DNA is a double helix
Background
DNA is the genetic code. It is passed from one generation to the next. It contains
information concerning the potential form and function of the organism.
The sequence of nucleotides of DNA makes each organism unique.
Procedure
1. Color your nucleotide (see instructor for key.)
2. Find a student with your complementary base pair.
3. Attach your nucleotide to its complementary base pair.
4. Add your joined nucleotides to the class DNA molecule.
5. Reinforce the molecule with scotch tape.
6. Answer all the analysis questions.
Analysis
1. What are the building blocks of DNA?
2. What are the three parts of a nucleotide?
3. What part of the nucleotide differs from one to the next?
4. What are the four nitrogenous bases?
FACT
A real DNA molecule may have three billion pairs of nucleotides. The sequence or
order of the nucleotides is the genetic code, and makes each individual organism unique.
5. What does DNA stand for?
6. Which N-base binds to thymine in DNA?
7. Which N-base binds to guanine in DNA?
8. Which N-base binds to adenine in DNA?
9. Which N-base binds to cytosine in DNA?
10. G binds with_____.
11.
C binds with_____.
12. A binds with_____.
13. T binds with_____.
FACTS
The shape of DNA is a double helix. Two long strands of nucleotides are arranged in
a twisted ladder shape. One strand is the template for the other strand of DNA. This
provides a mechanism for accurately replicating (duplicating) DNA. The N-base on one side
of the molecule is the complement of the N-base on the other strand of DNA.
14. The uprights of the DNA ladder are alternating _____________and _______________.
15. Extending from the ________ molecule on the nucleotide, _____________ pair with
their complements to form the rungs of the DNA ladders.
16. The rungs of the DNA ladder are held together by ____________ bonds.