1st Student's Major

Biological Sciences

1st Student's College

Science, Engineering and Technology

Students' Professional Biography

Chad Larson grew up in Worthington, MN and graduated from Worthington High School in May of 2001. He started attending Minnesota State University-Mankato in the Fall of 2002. He is currently majoring in Clinical Laboratory Sciences, Medical Technology with a minor in Chemistry.

Mentor's Name

Alison Mahoney

Mentor's Email Address


Mentor's Department

Biological Sciences

Mentor's College

Science, Engineering and Technology


New plant species develop when diploid plants (having two sets of chromosomes) spontaneously double their chromosomes and the resulting tetraploids (having four sets of chromosomes) are no longer able to back cross to diploid members of the population. The North American plant species Packera paupercula (balsam-leafed ragwort), is widespread and morphologically diverse. An isolated group of populations from the chalky soils of west-central Alabama was recently named Packera paupercula variety gypsophila (the chalk-loving balsam ragwort). The variety’s large diameter pollen grains suggest it may be tetraploid. This project attempts the first chromosome count for the variety by examining cells undergoing meiosis in the anthers (male sex organs) of flower buds. A “squash” is performed by dissecting out, staining, and pressing the anthers between a slide and cover slip and viewing the result with a microscope. If variety gypsophila is tetraploid, it may merit recognition as a new species.

Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License



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