Marigold Cell Size and Polyploidy

 

Tested Studies in Laboratory Teaching, 2004, Volume 25

Abstract

A majority of higher plants are polyploid, having more than two sets of chromosomes. Advantages of having extra chromosomes are not clear, and may vary among species and ecological niches, but one consistent effect is increased cell size. We present a lab using measurement of cell size to distinguish ploidy level among three marigold cultivars - a diploid, a triploid, and a tetraploid. The lab involves growing plants from seed, making surface impressions of leaf cells using fingernail polish, and measuring the size of guard cells using a microscope. It introduces students to plant leaf function, genetics, and microscope use.

Keywords:  ploidy, guard cell, stomate, marigold

University of Nevada, Las Vegas (2003)