Microbes and energy flow Flashcards
What is a population?
Individual microbial cells of a species proliferate to form a population
What is a community?
Populations interact/communicate to form communities
What is a microbiome?
All microorganisms and their genes within a particular enviroment
What is enrichment culture?
Providing the temp and chemical condition in the lab that encourages the growth of specific group of microbes
- Simulates real life conditions as closely as possible
When you you use an enrichment culture?
When there are a diverse amount of organisms living together, and want to get information about a specific subset of them
What is a chemoautotroph + some examples?
Chemoautotrophs are able to synthesize their own organic molecules from the fixation of carbon dioxide. These organisms are able to produce their own source of food, or energy. The energy required for this process comes from the oxidation of inorganic molecules such as iron, sulfur or magnesium.
- Hydrogen, sulfur, and nitrifying bacteria, some archaea
What two things are released when a bond is cleaved?
Energy is released as well as building blocks
How does NADP+ become reduced?
An external electron donor provides electrons e.g. H2S
NADP+ –> NADPH2 (reduction)
What are photoautotrophs + some examples?
Using energy from sunlight, carbon dioxide and water are converted into organic materials to be used in cellular functions such as biosynthesis and respiration.
- Plants, algae and cyanobacteria use H2O as an electron source to reduce CO2, producing O2 as a by-product (oxygenic)
- Green sulfur bacteria and purple sulfur bacteria use H2S a an electron source; they do not produce O2 (anoxygenic)
What are photoheterotrophs + some examples?
Photoheterotrophs obtain their energy from sunlight and carbon from organic material and not carbon dioxide
- Green nonsulfur bacteria and some purple nonsulfur bacteria, some archaea
What are chemoheterotrophs + some examples?
Chemoheterotrophs are unable to synthesize their own organic molecules. Instead, these organisms must ingest preformed carbon molecules, such as carbohydrates and lipids, synthesized by other organisms. They do, however, still obtain energy from the oxidation of inorganic molecules like the chemoautotrophs.
- Aerobic respiration: most animals, fungi and protozoa, and many bacteria
- Anaerobic respiration: some animals, protozoa, bacteria and archaea
- Fermentation: some bacteria, yeasts and archaea
What are primary producers?
Autotrophs - takes carbon and fixes it into a complex substrate
What are decomposers?
Heterotrophs - can break the carbon molecules down into CO2
- Cannot use these directly
- Recycles everything into the environment
What is noncyclic photophosphorylation?
Oxygenic
- Electrons flows from H20 (spliting of water because of sun energy) –> PS2 –> PS1 –> NADP+ = taken to other parts of the cell to produce ATP
- Generates O2, ATP and NADPH
What is Cyclic photophosphorylation
Anoxygenic
PS1 works in absense of PS2
- Generates ATP but no O2
- Electrons don’t come from water (H2S electron donor or other sources)
