example, have shown that wild organisms are almost exclusively red-eyed and
therefore cannot be hybridized. If a mutation with white eyes can be obtained,
however, and if that mutation is a genetically stable trait appearing across several
generations rather than one alone, it becomes possible to study the alleles through
cross-breeding. Mutations can be found in several traits besides eye color, including
eye and wing shape, but are exceedingly rare in the natural world. Through the use
of appropriate amounts of X-ray, ultraviolet, or other radiation, however, it may be
Fig. 2.5 Explanatory diagram for mendel’s hybridization experiment with genes presumed to
exist on chromosomes
2.2 Where Do Cells Exist in the Body?
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