Exam 13: Microbial Evolution and Systematics

Sequencing technology and molecular phylogenetic analyses have had very little impact on our understanding of the evolution and diversity of life on Earth.

Two eukaryotic organelles that are hypothesized to be the result of endosymbiosis are the ________ and the ________.

Why is the biological species concept useful for Eukarya but not meaningful for Archaea and Bacteria? How are prokaryotic species defined?

An important molecule in sequence-based evolutionary analyses of microbes are ________ genes.

The earliest RNA probably functioned in

Polyphasic taxonomy uses methods that include

Microbial species are difficult to define because they are seldom monophyletic.

Horizontal gene transfer is one plausible explanation as to why organisms in Archaea, Bacteria, and Eukarya still share so many genes among such distinct domains.

The atmosphere of primitive Earth is usually described as an oxidizing atmosphere.

It is believed that phototrophy arose approximately 3.3 billion years ago in

Molecular phylogeny and rRNA analysis provided the evidence used to separate Bacteria and Archaea into distinct domains.

You are studying 12 new isolates from the human skin. Their average nucleotide identity for shared orthologous genes is 97%.The isolates would most likely be

What characteristics make a gene a good candidate for determining the evolutionary relationships between organisms?

Which of the following is an assumption used in the molecular clock approach?

Carl Woese was an important figure in microbial classification and changed our understanding of the evolution and diversity of life. What breakthrough did he make that allowed us to infer evolutionary relationships between organisms? What assumptions was his breakthrough based on?

________ formed the semipermeable membrane-like surfaces for the earliest life forms.

At present there are four phyla in the domain Bacteria.

Microorganisms were probably restricted to the oceans and subsurface environments until