Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne DNA Extraction
Name: Kathleen
Status: Student
Age: 15
Location: N/A
Country: N/A
Date: N/A 

When a friend and I extracted DNA from 10 different fruits and vegetables for our Honors Bio project, we noticed that there was a lot of variation in the amounts of DNA yielded from each. Why do some things give more DNA than others?

There are several reasons that you find different amounts of DNA in each sample. One is that the number of cells per gram will be very different between different species of plants. Even within the same plant, the leaves will have different sized cells than in the roots or a fruit. But each cell within a plant will (usually) carry the same amount of DNA as every other.

The other neat thing is that many commercial plants are polyploid. That means they carry more than the usual two sets of chromosomes. While animals are usually diploid (two sets of chromosomes -- one from mom, one from dad), plants can be just about anything. For example, commercial wheat is hexaploid (six complete sets of chromosomes), and bananas are triploid (three sets).

Christine Ticknor
Ph.D. Student
Yale University
New Haven, Connecticut

Click here to return to the Molecular Biology Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory