Discuss how Hox gene number is related to body complexity.

The MyoD gene in mammals plays a role in muscle cell differentiation, whereas the Hox genes are homeotic genes that play a role in the differentiation of particular regions of the body. Explain how the functions of these genes are similar and different.

A computer simulation is used to predict the effect of a mutation in a Hox gene in fruit flies. Why is it important for the model to specify the timing of the mutation?

If a Hox 13 gene in a mouse was replaced with a Hox 1 gene, how might this alter animal development?

It has been hypothesized that in the evolution of vertebrates, there were two successive doublings of the genome (tetraploidization) to produce the vertebrate genome. a. How does the Hox superfamily fit with this hypothesis? b. Among vertebrates, there is variation in the numbers of genes present within the Hox gene family clusters. How could this variation arise?

How can hox genes provide evidence of evolution?

In evolution, why have small changes in Hox genes had a significant impact?

How are changes in Hox genes significant in the evolution of species?

How can hox genes help reveal how evolution occurred?

How can Hox genes help reveal how evolution occurred?

In the developing bud that gives rise to a hand in a human embryo, where would you expect the gremlin gene to be expressed?

If you were comparing the karyotypes of species that are closely related evolutionarily, what types of similarities and differences would you expect to find?

Genetic variation is prevalent in natural populations. This variation is revealed in the DNA sequencing of genes. According to the neutral theory of evolution, discuss the relative importance of natural selection against detrimental mutations, natural selection in favor of beneficial mutations, and neutral mutations in accounting for the genetic variation we see in natural populations.

For each of the following examples, discuss whether it would be the result of neutral mutation or mutation that has been acted on by natural selection, or both:
A. When comparing sequences of homologous genes, differences in the coding sequence are most common at the wobble base (i.e., the third base in each codon).
B. For a structural gene, the regions that encode portions of the polypeptide that are vital for structure and function are less likely to incur mutations compared to other regions of the gene.
C. When comparing the sequences of homologous genes, introns usually have more sequence differences compared to exons.