Four of the ten enzymes required for the biosynthesis of IMP are listed below. In which order do the reactions these enzymes catalyze occur during the synthesis of IMP?

1. IMP cyclohydrolase

2. GAR synthase

3. glutamine-PRPP amidotransferase

4. AIR carboxylase

#Question id: 11153

#Unit 9. Diversity of Life Forms

A researcher wants to determine the genetic relatedness of several breeds of dog (Canis familiaris). The researcher should compare homologous sequences of __________ that are known to be __________.

#Question id: 11152

#Unit 9. Diversity of Life Forms

When sufficient heat is applied, double-stranded DNA denatures into two single-stranded molecules as the heat breaks all of the hydrogen bonds. In an experiment, molecules of single-stranded DNA from species X are separately hybridized with putatively homologous single-stranded DNA molecules from five species (A-E). The hybridized DNAs are then heated, and the temperature at which complete denaturation occurs is recorded. Based on the data below, which species is probably most closely related to species X?

#Question id: 11151

#Unit 9. Diversity of Life Forms

What conclusion can be drawn validly from these data?

#Question id: 11124

#Unit 9. Diversity of Life Forms

A researcher compared the nucleotide sequences of a homologous gene from five different species of mammals with the homologous human gene. The sequence homology between each speciesʹ version of the gene and the human gene is presented as a percentage of similarity.

What probably explains the inclusion of rabbits in this research?

#Question id: 11123

#Unit 9. Diversity of Life Forms

Cladograms (a type of phylogenetic tree) constructed from evidence from molecular systematics are based on similarities in

#Question id: 11122

#Unit 9. Diversity of Life Forms

Phylogenetic hypotheses (such as those represented by phylogenetic trees) are strongest when