6. Chromosomal Variation

A species has 2n = 20. How many chromosomes will be found per mutant cell in an autotriploid organism.

How do we know that specific mutant phenotypes are due to changes in chromosome number or structure?

Consider synapsis in prophase I of meiosis for two plant species that each carries 36 chromosomes. Species A is diploid and species B is triploid. What characteristics of homologous chromosome synapsis can be used to distinguish these two species?

From the following list, identify the types of chromosome changes you expect to show phenotypic consequences.

Polyploidy

From the following list, identify the types of chromosome changes you expect to show phenotypic consequences.

Trisomy

Contrast the fertility of an allotetraploid with an autotriploid and an autotetraploid.

If the haploid number for a plant species is 4, how many chromosomes are found in a member of the species that has one of the following characteristics? Explain your reasoning in each case.

Hexaploidy

If the haploid number for a plant species is 4, how many chromosomes are found in a member of the species that has one of the following characteristics? Explain your reasoning in each case.

Tetraploidy

If the haploid number for a plant species is 4, how many chromosomes are found in a member of the species that has one of the following characteristics? Explain your reasoning in each case.

Triploidy

If the haploid number for a plant species is 4, how many chromosomes are found in a member of the species that has one of the following characteristics? Explain your reasoning in each case.

Octaploidy

If the haploid number for a plant species is 4, how many chromosomes are found in a member of the species that has one of the following characteristics? Explain your reasoning in each case.

Pentaploidy

If the haploid number for a plant species is 4, how many chromosomes are found in a member of the species that has one of the following characteristics? Explain your reasoning in each case.

Diploidy

Describe the origin of cultivated American cotton.

Mating between a male donkey (2n = 62) and a female horse (2n = 64) produces sterile mules. Recently, however, a very rare event occurred—a female mule gave birth to an offspring by mating with a horse.

Why is it very unlikely that the offspring will have fully horse-like genetic characteristics?

Mating between a male donkey (2n = 62) and a female horse (2n = 64) produces sterile mules. Recently, however, a very rare event occurred—a female mule gave birth to an offspring by mating with a horse.

How many chromosomes does the mule–horse offspring carry?