BIOL211#2(2)

BIOL211#2(2) - 8/16/2011 Chapter 27 Introduction...

Info iconThis preview shows pages 1–4. Sign up to view the full content.

View Full Document Right Arrow Icon
8/16/2011 1 Chapter 27 Bacteria and Archaea Introduction Prokaryotic Simple cell structure Smallest known cells Live in nearly every conceivable habitat Earth’s oldest organisms Exceedingly diverse Figure 27.1 Diversity and Evolution Have a great genetic diversity – Two strains of E. coli are genetically more diverse than a human and a platypus Duck-Billed Platypus Domain Archaea – Possess features common with eukaryotes Presence of histone proteins in DNA – Have membrane lipids with ether linkages Resist damage by heat and extreme conditions Some live in extreme habitats and are known as extremophiles Hyperthermophiles – Thrive in very hot environments – Some survive temperatures of 121 C – May produce methane – Often metabolize sulfur
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
8/16/2011 2 Halophiles – Live in highly saline environments – Found in the Great Salt Lake and the Dead Sea Dead Sea Great Salt Lake Domain Archaea Kingdoms Korarchaeota Euryarchaeota Crenarchaeota Nanoarchaeota Domain Bacteria – Includes most known prokaryotes – Most live in moderate habitats – Many form symbiotic associations – Includes pathogenic and beneficial species Table 27.1 Proteobacteria – Amazing diversity of form and metabolism Rhizobium form beneficial associations with the roots of legume plants Agrobacterium cause destructive galls on plants Nitrosomonas is an important component of the global nitrogen cycle Proteobacteria Niesseria gonorrhoeae is the causative agent of gonorrhea Vibrio cholerae causes cholera Salmonella enterica and Escherichia coli cause human disease Helicobacter pylori cause stomach ulcers
Background image of page 2
8/16/2011 3 Cyanobacteria – Contains abundant photosynthetic bacteria – Named for blue-green (cyan) coloration – The only prokaryotes that generate oxygen – Produced the Earth’s first oxygen-rich atmosphere, which allowed the rise of eukaryotes Cyanobacteria – Display the greatest structural diversity among bacterial phyla
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 4
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 9

BIOL211#2(2) - 8/16/2011 Chapter 27 Introduction...

This preview shows document pages 1 - 4. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online