MICR 271 Module 5 Practice Exam Questions With Practical Answers Graded A+.

Most of the microorganisms found in dry valleys of Antarctica are ________________ and thrive in what would otherwise appear to be an inhospitable environment. - correct answer prokaryotic TRUE OR FALSE: marine microbes form the base of the food chain and are the major players in controlling the health of the marine ecosystem. - correct answer True TRUE OR FALSE: microbial diversity correlates with habitat diversity. - correct answer True Bioluminescence communication 'system' is used to manipulate the behaviour of host organisms. Some bacteria, in symbiotic relationships with their hosts, use it to do what? - correct answer facilitate searching for prey, finding mates, deter predators, help to camouflage the host Organisms living in the deep sea interact using what ability? - correct answer bioluminescence What is an example of an ecosystem thriving under extreme conditions that includes immense diversity is the...? - correct answer hydrothermal vents in the deep sea TRUE OR FALSE: although tropical coral reefs cover only 0.5% of the ocean floor, they contain 50% of the marine life. - correct answer False, 25% of the marine life. Where are high concentrations of marine viruses found? - correct answer in the shallow areas around coral reefs It has been found that viral-mediated lysis of their hosts release ____________ organic matter & _____________ organic matter into the reef water column & the ________ compartment, making them available to other microorganisms & coral. When is this mechanism especially important? - correct answer -dissolved, particulate, benthic -when resources are limited Microbes are frequently associated with the _______ of a plant, but can confer resistance to pathogen in the parts of the plant above ground. - correct answer roots TRUE OR FALSE: many of the microbes found in close association with plant roots are considered to be commensals as they don't appear to have a direct effect on the plant. - correct answer True Would microbes that fix nitrogen have a direct positive effect on the plant? - correct answer yes How do pathogenic microbes damage a plant? - correct answer via infection or production of phytotoxic compounds TRUE OR FALSE: all active microbes will affect other microbes and through a complex of interactions indirectly affect either plant or pathogen. - correct answer True Beneficial microbes either ___________ plant growth directly or ___________ the plant by inhibiting delitrious microbes or through induced systemic resistance. - correct answer promote, protect What is the rhizosphere? - correct answer narrow region of soil that is indirectly influenced by root excretions & associated soil microorganisms Pseudomonas is not only a human pathogen; it can be beneficial, depending on where...? - correct answer it forms biofilms Kudzo Bug: interaction between animal behaviour and microbe and what does it mean? - correct answer Interaction btwn animal behaviour & microbe -when born, bugs feed on capsules of organisms that live w/in the bug as symbionts; if no capsules are present, nymphs wander in search of microbes What does it mean? -behaviours of animals can shape symbiont acquisition Green Iguana: microbial species or consortium, interaction between animal behaviour and microbe, what does it mean? - correct answer Microbial species: Gut microbiota Interaction btwn animal behaviour & microbe: -juvenile iguanas eat soil or feces to tailor the microbiota to their current diet What does it mean? -animals may adjust microbiota at different life-history stages Bobtail Squid: interaction between animal behaviour and microbe, what does it mean? - correct answer Interaction btwn animal behaviour & microbe: -squids eject bioluminescent bacteria daily What does it mean? -suggests animals can actively control their symbiont populations Fruit Fly: microbial species, interaction between animal behaviour and microbe, what does it mean? - correct answer Microbial species: Gut microbiota