Biology - HOT Science Lab

Student
Building a DNA Model Project
(Adapted from: Prentice Hall - Laboratory Manual A)
NGSSS:
SC.912.L.16.3 Describe the basic process of DNA replication and how it relates to the
transmission and conservation of the genetic information. (AA)
Background Information:
DNA, deoxyribonucleic acid, is found in the chromosomes of all living things. The structure of
this molecule encodes the genetic information that controls the development of each living thing.
When scientists figured out the structure of DNA, they built a model. The structure of this model
helped them see how DNA can carry information and be copied to make new DNA molecules. In
this investigation you will examine the structure of DNA by building your own DNA model.
The DNA molecule is the shape of a double helix (spiral). The molecules making up DNA are
deoxyribose, phosphate, and four nitrogenous bases: adenine, thymine, cytosine, and guanine.
These are called nucleotides. Adenine and guanine are purines and cytosine and thymine are
pyrimidine. They are also known by their code letters of A, G, T, and C. There is a specific
manner in which they bond A only to T and C only to G.
Problem Statement:
If during replication a base pair gets substituted, then what effect might it have on the DNA
molecule
Safety: Do not eat any of the edible food items used in this lab.
Pre-Lab Questions:
1. Which two molecules make up the ―sides‖ of a DNA molecule
2. When you construct your model of DNA, which materials will you use to represent the
sides of a DNA molecule
3. Which molecules make up the ―rungs‖ of a DNA molecule
When you construct your model of DNA, which materials will you use to represent the
rungs of a DNA molecule
4. Which bases usually pair together to form the rungs of a DNA molecule
Vocabulary: double helix, nucleotide, purines, pyrimidines, DNA replication, DNA polymerase,
mutation
Materials (per group):
2 strips of cardboard, 38 cm x 3 cm
Metric ruler
Toothpicks
Crayons
Tape
Colored gumdrops
Modeling clay
Digital camera (optional; if available)
Colored printer (optional; if available)
Biology HSL Page 195
Curriculum and Instruction