Micro Test #3

The goal of wastewater treatment is to

reduce organic and inorganic materials in wastewater to a level that no longer supports microbial growth

The metabolic process of denitrification

reduces NO3-.

The phylogenetic analysis of complex microbial communities often targets small subunit (SSU) ribosomal RNA genes. This is because rRNA is found in all organisms and __________.

is highly conserved over evolutionary time

Which of the following environmental and host factors influence the composition of resident microflora on the skin?

age, weather, and personal hygiene

Which of the following does NOT affect pathogen growth?

availability of nitrogen gas

The function of leghemoglobin in root nodules is to

bind oxygen

Two organisms that both benefit from each other are in a symbiotic relationship called

mutualism

Some organisms are capable of using aerobic respiration or anaerobic respiration but use aerobic respiration preferentially. Why do they use aerobic respiration when possible? Correct!

Respiration with oxygen as a terminal electron acceptor generates more energy than respiration with other terminal electron acceptors.

The Calvin cycle

1.requires both ribulose biphosphate carboxylase and phosphoribulokinase 2. responsible for the fixation of CO2 into cell material 3.utilizes both NAD(P)H and ATP 4. uses CO2, NAD(P)H, and ATP to make biomass with ribulose biphosphate carboxylase and phosphoribulokinase

Which is the MOST toxic form of mercury?

CH3Hg+

Decomposition of organic carbon ultimately results in the formation of __________.

CO2 in aerobic environments and CO2 plus CH4 in anoxic environments

Environmental damage due to acid mine drainage occurs only once ores containing pyrite (FeS2) are __________.

exposed to oxygen and water

The body's non-inducible, preexisting ability to recognize and destroy pathogens or their products is called

innate immunity

Bacterial abundance (102 to 108) and generation times (days to centuries) vary by many orders of magnitude in the deep subsurface mainly due to __________.

nutrient limitations

Pathogenicity is the ability

of the pathogen to inflict damage on the host.

Microenvironments of soil exist where ________ concentrations greatly vary.

oxygen, nitrate and sulfur

Which treatment method(s) are used in primary wastewater treatment?

physical separation

Which of the following represents increasing microbial diversity?

population-guild-community

Which choice provides the steps in drinking water treatment in the correct order?

sedimentation, coagulation, filtration, disinfection, storage

Enrichment cultures are often effective for isolating bacteria from complex communities in natural samples because they __________.

select both for and against certain bacteria

While most of the oil spilled into the Gulf of Mexico from the Deepwater Horizon drilling rig in 2010 has disappeared, some of the oil spilled from the Exxon Valdez oil tanker into Prince William Sound, Alaska, in 1989 still remains in the coastal sand and sediments. What possible differences in these two spills could account for the different rates of petroleum degradation?

temperature and the types of hydrocarbons present

All AB toxins have which of the following?

two subunits

Compounds that are NOT produced by organisms anywhere in nature are called __________.

xenobiotic