Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Unit Chapters
Proteins & Proteomics
Evolution & Phylogenetics
Microbial Diversity
Emerging Infectious Diseases
Why Do Diseases Emerge?
The Human Body as an Ecosystem
The Emergence of Antibiotic-Resistant Bacteria
Mechanisms of Resistance
Microbial Adaptation and Change
Lateral Gene Transfer
Travel, Demographics, and Susceptibility
New Technologies
Animal Reservoirs
Insect Vectors
Climate and Weather
Preventing and Controlling Emerging Infectious Disease
Genetics of Development
Cell Biology & Cancer
Human Evolution
Biology of Sex & Gender
Genetically Modified Organisms
Microbial Adaptation and Change

The evolution of novel microbes, including antibiotic-resistant strains, depends on diverse members of microbial populations that can thrive in new conditions. Microbes have incredible abilities to change their genetic make-up and evolve faster than their hosts do. Multiple mechanisms ensure the diversity that allows for expansion.

The production of a single, novel gene product may be the key to bacterial survival; however, several gene products working together sometimes provide the advantage. Mutation generates new genes but, unlike higher eukaryotes, bacteria do not undergo sexual reproduction; the typical bacterium simply grows, replicates its DNA, and divides. Therefore, bacterial reproduction does not provide a mechanism for generating progeny with new combinations of genes. How, then, do bacteria obtain new gene assortments, some of which may provide survival?

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