Why are molecular approaches important to the field of microbial taxonomy and phylogeny? Phylogenetic inferences based on molecular approaches provide the most robust analysis of microbial evolution currently available. It allows for the collection of a large and accurate dataset from many organisms Almost no fossil record was left by microbes when compared to plants and animals All of the above None of the above

To construct a phylogenetic tree by applying the principles of parsimony to molecular sequence data, one would: a. start by making assumptions about variations in the rates atwhich different DNA segments evolve. b. group together organisms that share the largest number ofancestral sequences. c. group together organisms that share derived sequences, matching the groups to those defined by morphologicalcharacters. d. group together organisms that share derived sequences, minimizing the number of hypothesized evolutionarychanges. e. identify derived sequences by studying the embryology of theorganisms.

What does the trunk of the classic phylogenetic tree represent? single common ancestor pool of ancestral organisms new species old species

Which of the following is not a fossil? a. Dried-out animal bones in a layer of desert sand b. A patch or fur encased in amber c. A woolly mammoth frozen in Arctic permafrost d. Remains of an extinct whalelike animal e. The impression of a p1ant leaf in sandstone f. The wrinkly texture of shale imprinted with biofilms in sediments

Where in a phylogenetic tree would you expect to find the organism that had evolved most recently? at the base within the branches at the nodes at the branch tips

Figure 1.7 Taxonomic classification of five species that are related at different levels. Each species has been assigned to ever more inclusive groups, or taxa: in this case, from genus to domain. From the left, Joaquim Gaspar; kymkemp.com; Sylvie Bouchard/Shutterstock.com; Courtesy of Melissa S. Green, www.flickr.com/photos/henkimaa; Grodana Sarkotic. Figure It Out: Which of the plants shown here are in the same order?

List the different levels of the taxonomic classification system.

What type of micrograph is shown below? Is the organism pictured prokaryotic or eukaryotic? How can you tell?

Which category falls immediately below class in the systematic hierarchy? a. species b. order c. family d. genus e. phylum

What is true about organisms that are a part of the same clade? They all share the same basic characteristics They evolved from a shared ancestor They usually fall into the same classification taxa They have identical phytogenies.