Genome size of man and animals relative to the plant Allium cepa
Abstract:
A direct Feulgen-cytophotometric comparison of the genomic DNA content (C value) was performed between the liliaceous plant species Allium cepa and a number of animal species to reassess the genome size ratios between plants and animals. These appeared unduly ambiguous as a consequence of divergent picogram estimates in several animal reference species. Taking 1C = 16.75 pg for Allium cepa, the estimates were (1C value in picograms): man, 3.11; Indian muntjak CCL 157 cell line, 2.68; domestic pig, 2.79; Chinese hamster, 2.66; CHO cell line, 2.73; laboratory rat, 2.65; mouse, 3.04; rat kangaroo Pt-K2 cell line, 4.21; fowl, 1.16; and the green toad, 4.30. These values are consistent with a number of independent absolute and relative DNA content determinations reported for animals, and therefore define a coherent set of animal and plant reference values for genome size determinations.
Related Concept Videos
Genomic DNA in Eukaryotes
Plant Breeding and Biotechnology
Trihybrid Crosses
Some of Mendel’s crosses examined three pairs of contrasting characteristics. Such a cross is called a trihybrid cross. A trihybrid cross is a combination of three individual monohybrid crosses. For example, plant height (tall vs. short), seed shape (round vs. wrinkled), and seed color (yellow vs. green).
The F1 generation plants of a trihybrid cross are heterozygous for all three traits and produce eight gametes. Upon self-fertilization, these gametes have an equal chance to...


