Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Unit Chapters
Genomics
Proteins & Proteomics
Evolution & Phylogenetics
Microbial Diversity
Introduction
Microbes as the First Organisms
The Diversity of Microbial Metabolism
Archaea and Bacteria
The Universal Tree of Life
Studying Unculturable Microbes with PCR
Microbes and the Carbon Cycle
Microbes and the Cycling of Nitrogen
Biofilms
Biofilms Formation and Bacterial Communication
Impact of Biofilms on Humans
Communication Between Bacteria and Eukaryotes
Microbes in Mines
Microbial Leaching of Ores
Coda
Emerging Infectious Diseases
HIV & AIDS
Genetics of Development
Cell Biology & Cancer
Human Evolution
Neurobiology
Biology of Sex & Gender
Biodiversity
Genetically Modified Organisms
Coda

There are about 5,000 known species of prokaryotes, but scientists estimate that true diversity could range between 400,000 and 4 million species. Each has adapted to its particular environment and each performs many roles. Some of these roles are essential to sustaining entire ecosystems. But what is a prokaryotic species? Microbes, which reproduce asexually, cannot be thought of in terms of reproductive isolation. The advent of molecular genetics has brought with it new approaches to defining the concept of species. Some bacteriologists are differentiating prokaryotic species based on their rRNA sequences. If organisms possess rRNA sequences that differ by more than a certain proportion (usually three percent), these bacteriologists consider them different species. As new molecular genetic approaches to the study of microbes are developed, scientists will find additional ways of describing the vast diversity of organisms that make up a parallel, albeit invisible, part of our world.

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