Download Metabolic strategies

A look at Metabolism
What do we know so far about
cells?
• Cells are the basic units of life
• Cells all contain DNA which is the genetic
code for proteins
• Cells share metabolic processes necessary
to generate energy (ATP)
What is metabolism?
• Sum total of all chemical reactions in a cell
• Catabolic reactions-breaking down of large
complex compounds, generating ATP
• Anabolic reactions-building complex
compounds from simple ones, requires ATP
Metabolism
All cells need a source of carbon
• Organic compounds as a source
– Heterotrophs
• Carbon dioxide as a source
– Autotrophs
All cells need a source for energy
(ATP)
• Light as the energy source
– Phototrophs
• Breaking of chemical bonds to generate
ATP
– Chemotrophs
Since cells need both carbon and
energy…combine the terms
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Photoautotrophs
Photoheterotrophs
Chemoautotrophs
Chemoheterotrophs
Energy and Carbon sources
Photoautotroph: Cyanobacteria
Photoheterotroph: Chloroflexus
(green nonsulfur bacteria)
Photoheterotroph:
Rhodopseudomonas (purple non
sulfur)
Chemoautotrophs: Beggiatoa
Chemoheterotroph: E. coli