A hybrid allotetraploid species (2n = 60)was backcrossed to one of the suspected parents (2n = 30).When the F₁ underwent meiosis,the prophase chromosome configuration was examined.If the guess about the suspected parent was correct,what would the chromosome configuration look like?

Question

Quizplus · Accepted Answer

If the hybrid allotetraploid species was backcrossed to one of the suspected parents (2n = 30), each gamete of the hybrid would contain half of the 60 chromosomes (30 chromosomes), which is equivalent to a haploid chromosome number of the suspected parent.

During meiosis, the chromosomes would pair up, forming 15 sets of homologous chromosomes (30 chromosomes in total). The remaining 30 chromosomes would be unpaired, resulting in 30 single chromosomes.

Therefore, the correct chromosome configuration would be 15 pairs and 30 singles, which is equivalent to choice D (15 pairs and 15 singles).

A Hybrid Allotetraploid Species (2n = 60)was Backcrossed to One