ch 27

Question 1

mycorrhizae

Answer 1

fungi living in close association w plant roots- extends surface area of roots

Question 2

biochemical cycle

Answer 2

recycling (oxidation and reduction) of chemical elements

• carbon cycle
• nitrogen cycle
• sulfur cycle
• phosphorus cycle

Question 3

carbon cycle

Answer 3

fixation and respiration

1. CO2 in atmosphere used by plants
2. plants eaten by animals
3. decomposition of dead plants and animals
4. soil and water microbes (fossil feuls0
5. burning and respiration release back into atmosphere

Question 4

nitrogen cycle

Answer 4

ammonification, fixation, nitrification, and denitrification
1. free nitrogen gas in atmosphere taken up by legume
2. fixed into ammonia
3. goes through nitrification
4. released back into atmosphere
uses decay organisms-> aerobic, anaerobic, and denitrifying bacteria, and fungi

Question 5

sulfer cycle

Answer 5

1. dissimilation
2. assimilation
3. oxidation
4. anaerobic respiration

Question 6

phosphorus cycle

Answer 6

found in rocks and cells

-insoluble phosphorus processed by thiobacillus

Question 7

nitrogen fixation

Answer 7

rhizosphere, root nodules, and lichens

Question 8

xenobiotics

Answer 8

resistant to degradation

Question 9

positive examples of microbes on nutrient cycle or removal of pollutants

Answer 9

1. bioremediation
2. bioaugmentation
3. composting

Question 10

bioremediation

Answer 10

use of microbes to detoxify or degrade pollutants, enhanced by nitrogen and phosphorus fertilizer

Question 11

bioaugmentation

Answer 11

addition of specific microbes to degrade of pollutant

Question 12

composting

Answer 12

arranging organic waste to promote microbial degradation by thermophiles

Question 13

freshwater microbiota- littoral zone

Answer 13

along shore

producers- plants

Question 14

freshwater microbiota- limnetic zone

Answer 14

surface of open water along shore

producers- algae and cyanobacteria

Question 15

freshwater microbiota- profundal zone

Answer 15

deeper water, under limnetic zone

producers- anaerobic purple and green photosynthetic bacteria

Question 16

freshwater microbiota- benthic zone

Answer 16

bottom sediment, often no light and little oxygen

producers- desulfovibrio, methanogens, clostridium

Question 17

seawater microbiota

Answer 17

phytoplankton in top 100m
archaea below 100m
bioluminescent bacteria

Question 18

microbial water pollution

Answer 18

microbes are filtered from water that percolates into groundwater
some pathogens are transmitted to humans in drinking and recreational water

Question 19

chemical water pollution

Answer 19

resistant chemicals may be concentrated in the aquatic food chain (example mercury)

Question 20

eutrophication

Answer 20

overabundance of nutrients in lakes and streams caused by the addition of organic or inorganic matter (cause algal blooms)

Question 21

biochemical oxygen demand (BOD)

Answer 21

bacterial decomposition of organic matter uses up oxygen in the water

Question 22

municipal sewage treatment

Answer 22

1. primary treatment- removal of solids, disinfection
2. secondary treatment- removal of much of BOD, disinfection, water can be used for irrigation
3. tertiary treatment- removal of remaining BOD, nitrogen, and phosphorus, disinfection, water is drinkable

Question 23

coliforms

Answer 23

aerobic or faculative anaerobic gram-negative, endospore forming rods that ferment lactose to acid plus gas within 48 hrs at 35C