Chapter 11 - Microbial Ecosystems Flashcards
Interactions + exchanges of materials between organisms + their surrounding environment=
Ecosystems
An ecosystem consists of ___________ of organisms living in a specific area, interacting with each other + the environment.
communities
_______ _________ capture energy through photosynthesis (usually autotrophs).
Primary producers
_________ (heterotrophs) ingest/utilize stored photosynthetic energy.
Consumers
___________ recycle components back into environments.
Decomposers
Members of communities can be grouped into functional groups called ______ based on the processes that they carry out.
guilds
Specific functional role of an organism within an ecosystem =
Niche
Groups/ layers of microbes on a surface that interact with and support each other =
biofilms
A mechanism of intercellular communication that regulates the formation of biofilms =
quorum sensing
Microbes secrete _________________ to protect the biofilm and form channels for transport of nutrients and wastes.
exopolysaccharide (EPS)
Only _____% of the microbial species on Earth have been grown in culture.
1-5
The greatest microbial diversity in terrestrial environments is found in ______ (6,000-40,000).
soil
The extraction of DNA from the environment, followed by PCR and sequencing small subunit rRNA =
Direct sequencing
DNA from an environmental sample is used to construct a genomic library =
metagenomics
________ in ecosystems = “number of species”
Diversity
Over 98% of the oceans biomass is ___________.
microbial
Most marine microbes exist in ____________, a process of using nutrients at very low concentrations.
oligotrophy
The process by which an entire body of water becomes enriched with nutrients and minerals (leads to “overfeeding” and anoxic waters) =
eutrophication
Areas without enough oxygen to support much Eukaryal life (hypoxic conditions) =
Dead Zones
The ___________ ____________ of the ocean = phytoplankton in the surface zone (contributes to the oxygenation of the water).
Primary producers
Average seafloor depth = _______ meters
3,500
Microbes that can withstand/require intense pressure to grow =
piezophiles
Approximately _% of primary production reaches the seafloor.
1
There are 10 times more ________ existing in the oceans than microbes.
viruses
Freshwater ecosystems can be ___________ (oxic epiliumnion, thermocline, anoxic hypolimnion).
stratesfied
Categories of ecosystems based on vegetation characteristics =
biomes
organics from soil =
humic substances
Region of soil immediately surrounding plant roots possessing large amounts of carbon (higher # of microbes) =
rhizosphere
The use of microbes to consume and remove human-made materials from soil =
bioremediation
Studying microbes discovered in deep-sea vents, hot springs, oil wells & goldmine subterranean rock =
deep subsurface microbiology
Minerals and gases released from volcanic activity is used as energy for carbon fixation =
hydrothermal vents
