Polymerase Chain Reaction Activity
Gorton High School
Summer Research Program for Science Teachers
Subject: Living Environment
Grade Level: 9th and 10th
Unit: Genetics, Biotechnology, lab skills
Objective: Students will be able to:
denaturation, primers, replication, template, polymerase, PCR
Prior Knowledge: Teacher discussion on DNA replication, protein synthesis and the function and structure of the DNA molecule.
Introduction: To study genes scientists need a large quantity of DNA. PCR is a biotechnology technique that can produce many copies of a targeted DNA sequence. The process will replicate a small quantity of DNA in just a few hours. What are the ingredients to do a PCR? All you need is a targeted DNA strand, primers, enzymes and three different temperature chambers.
a) The target DNA strand is heated (about 94ºC). DNA paired strands are separated and become single strands.
b) Primers, short segments of DNA, are added and bound to the targeted single strands by complementary base pairing. This reaction occurs at a cooler temperature (about 50-65ºC).
c) An enzyme, Taq polymerase, is added to the reaction at a higher temperature (about 72ºC). It binds at the primer site and copies the sequence of that strand. Within a short period of time it replicates the targeted DNA strand.
d) This completes the first cycle and the above steps are repeated until you have many copies of the desired gene.
Making a model of DNA handout
DNA review worksheet
Time: Three class periods-45 minutes
Day One – construct a DNA template
Day Three – PCR Activity
New York State Science Standards
Standard 1 Key Idea 1-performance indicator 1.1b
Key Idea 2-performance indicator 2.2a
Standard 4 Key Idea 2-performance indicators 2.1a, 2.1b, 2.1c, 2.2c, 2.2d, 2.2e
Key Idea 5- performance indicators 5.1f, 5.1g