Deck 24: Microbes and the Environment

Question 1

The conversion of nitrate (NO₃^-) to nitrogen gas (N₂) is called ______.

A)photosynthesis
B)ammonification
C)denitrification
D)nitrogen fixation
E)nitrification

Answer 1

C

Question 2

The thin envelope of life that surrounds the earth's surface is called the ______.

A)hydrosphere
B)lithosphere
C)biosphere
D)atmosphere
E)ecosystem

Answer 2

C

Question 3

The oxidation of ammonia (NH₄⁺) to nitrate (NO₃^-) and nitrite (NO₂^-) is called ______.

A)nitrogen fixation
B)nitrification
C)ammonification
D)photosynthesis
E)denitrification

Answer 3

B

Question 4

Phytoplankton is composed of protozoa and small invertebrates.

Question 5

You have been using massive amounts of weed killer and insecticide to kill weeds in your yard, as well as the grubs and aphids that are munching on your roses and your grass.What effect might this have from a microbiological standpoint?

A)Loss of microbial diversity in the soil
B)Reduction in microbial numbers in the soil
C)Damage to the nitrogen fixing bacteria
D)Damage to the mycorrhizae
E)All of the above may be effects of this practice.

Question 6

The physical location in the environment to which an organism has adapted is its ______.

A)biome
B)community
C)habitat
D)niche
E)population

Question 7

A group of organisms of the same genus within a community is called a ______.

A)biome
B)community
C)habitat
D)niche
E)population

Question 8

The study of interactions between microbes and their environment and how those interactions affect the earth is called ______.

A)applied microbiology
B)bioengineering
C)microbial ecology
D)industrial microbiology
E)biotechnology

Question 9

The full extent of the diversity and abundance of life on earth has only been understood in the past few years as a result of

A)microscopy techniques to identify the vast quantity of viruses present in all environments.
B)advances in deep oceanography and deep earth mining engineering.
C)environmental movements to preserve parks, coral reefs, and glaciers.
D)techniques to identify organisms that do not rely on culturing.

Question 10

Living or dead organisms that occupy an organism's habitat are called biotic factors.

Question 11

Which environment represents the largest pool of microbial genes?

A)Rainforest
B)Freshwater lakes
C) Oceans
D) Soil
E) Humans and animals

Question 12

The conversion of gaseous nitrogen (N₂) to ammonia (NH₄⁺) occurs during ______.

A)denitrification
B)nitrogen fixation
C)ammonification
D)nitrification
E)photosynthesis

Question 13

The terrestrial realm of the biosphere is distributed into particular climatic regions called ______.

A)populations
B)communities
C)habitats
D)niches
E)biomes

Question 14

The major group of organisms that fix nitrogen into ammonia and then oxidize it to nitrate are ______.

A)bacteria
B) fungi
C) protozoa
D) algae

Question 15

Why are waterlogged soils often infertile?

A)The lack of physical space in this type of soil blocks bacterial growth.
B)Water molecules are used instead of oxygen for cellular respiration.
C)There is less carbon in waterlogged soil than dry soil.
D)Nitrifying bacteria require oxygen, and the excess water takes the place of oxygen-containing air.

Question 16

The study of the practical uses of microbes in various industries and technologies is ______.

A)applied microbiology
B)bioengineering
C)industrial microbiology
D)biotechnology
E)microbial ecology

Question 17

A collection of organisms, together with the physical and chemical factors in their environment, are called a(n) ______.

A)hydrosphere
B)lithosphere
C)ecosystem
D)atmosphere
E)biosphere

Question 18

The primary role of producers is the recycling of nutrients in an ecosystem.

Question 19

Both energy and nutrients cycle through an ecosystem.

Question 20

Scientists have learned the full extent of viral abundance on earth because

A)the final step of the viral life cycle, release of mature viruses and cell lysis, releases millions of viruses.
B)metagenomic sequencing has identified viruses in a broad variety of environments.
C)a wide variety of microbes is available to act as hosts for these viruses.
D)viruses are known to grow on all life forms: animal, plant, fungi, and bacteria.

Question 21

Which of the following organisms anaerobically reduces sulfates to hydrogen sulfide or metal sulfide?

A)Thiobacillus ferrooxidans
B)Nitrosococcus
C)Desulfovibrio
D)Thiobacillus thiooxidans
E)Rhizobium

Question 22

Chemical elements needed in trace amounts for biochemical reactions have a biogeochemical cycle, including boron, chromium, manganese, and cobalt.

Question 23

When methanogens convert carbon dioxide to methane, it is a(n) ______ reaction.

A)aerobic
B)oxidation
C)reduction
D)ammonification

Question 24

Which of the following statements regarding the phosphorus cycle is incorrect?

A) Phosphorus is released naturally by mining.
B)The phosphorus pool is in sedimentary rock.
C) Phosphorus mineralization occurs by microbial action.
D)Thiobacillus produces sulfuric acid that dissolves phosphate rock.
E)Phosphorus must be phosphatized to enter biological systems.

Question 25

Heterotrophs include

A)producers only.
B)consumers only.
C)consumers and decomposers.
D)producers and consumers.
E)producers, consumers, and decomposers.

Question 26

Organisms that inhabit soil or water and breakdown and absorb the organic matter of dead organisms are called ______.

A)autotrophs
B)decomposers
C)secondary consumers
D)primary consumers

Question 27

Carbon dioxide (CO₂) is

A)removed from the atmosphere during photosynthesis.
B)a source of carbon for autotrophs.
C)returned to the atmosphere during respiration and fermentation.
D)used by marine organisms to make limestone for their hard shells.
E)All of the choices are correct.

Question 28

The advantage of nitrogen fixation to the host plant is

A)the ability to synthesize amino acids and proteins from the ammonia produced.
B) the production of nucleotides required for nucleic acid synthesis.
C) the production of antibiotics that protect the plant against pathogenic soil bacteria.
D) the ability to use nitrogen gas instead of oxygen gas in cellular respiration, particularly when the soil is compacted.

Question 29

Toxic substances accumulate through natural trophic flow of an ecosystem.

Question 30

The energy of the sun is converted into chemical energy during ______.

A)nitrification
B)denitrification
C)photosynthesis
D)ammonification
E)nitrogen fixation

Question 31

Organisms whose sole source of carbon for growth is CO₂ are called ______.

A)consumers
B)autotrophs
C)decomposers
D)saprophytes
E)lithotrophs

Question 32

Which of the following statements regarding biogeochemical cycles is incorrect?

A)Recycling keeps nutrients in balance.
B)All elements originate from a nonliving, long-term reservoir.
C)All organisms directly participate in recycling.
D) Cycles are simple systems between living and nonliving components.
E)Elements cycle through biotic and abiotic environments.

Question 33

There are very few viruses in aquatic environments.

Question 34

Which organism is a nitrogen-fixing symbiont of legumes?

A)Clostridium
B)Pseudomonas
C)Rhizobium
D)Nitrobacter

Question 35

Which of the following is a source of methane?

A)Gastrointestinal tract of cattle and sheep
B)Photosynthesis from halophiles in the Dead Sea
C)Decomposition of organic detritus on the forest floor
D)Degradation of cellulose and lignin by fungi
E)All of these processes produce methane.

Question 36

The combustion of fossil fuels, such as coal, oil, and gas, have contributed to the steady increase in atmospheric CO₂ gas over the last 25 years.

Question 37

Which crop plant would likely have a mutualistic relationship with Rhizobium bacteria?

A)Potatoes
B) Peas
C)Corn
D) Wheat
E) Cotton

Question 38

A Paramecium is an example of a ______.

A)primary consumer
B)primary producer
C)quaternary consumer
D)tertiary consumer
E)secondary consumer

Question 39

Which trophic level forms the base of a food chain?

A)Primary producers
B)Quaternary consumers
C)Tertiary consumers
D)Secondary consumers
E)Primary consumers

Question 40

Methane is a significant part of the carbon cycle in ______ environments dominated by methanogens.

A)autotrophic
B)anaerobic
C)thermophilic
D)oligotrophic

Question 41

The slowly decaying organic litter from plant and animal tissues that is found in the soil is called ______.

A)the lithosphere
B)detritus
C)aggregate
D)a biofilm

Question 42

Most of the organic sulfur is located in

A)nucleotides and nucleic acids.
B)monosaccharides and carbohydrates.
C) amino acids and proteins.
D)fatty acids and lipids.

Question 43

The majority of Earth's water is found in ______.

A)icecaps and glaciers
B)oceans
C)freshwater lakes
D)soil moisture
E)ground water

Question 44

You have been diagnosed with neurotoxic poisoning after having ingested an algal toxin, called brevetoxin, produced by Karenia brevis.In which food did you likely consume this?

A)Freshwater trout
B)Canned tuna
C)Oysters
D)Tomatoes

Question 45

Which of the following processes is not a part of metagenomic analysis of an environment?

A)Reverse transcription
B)DNA sequence assembly
C)Extraction of DNA from original sample
D)High-throughput sequencing
E)Polymerase chain reaction

Question 46

You have drained a pond on your property to make it deeper.In the process of using a machine to dig, you find that the mud is black and smells terrible.Your prediction is that ______ bacteria predominate in this area of the mud.

A)denitrifying sulfur-reducing
C)sulfur-oxidizing
D)nitrifying
E)nitrogen-fixing

Question 47

Vast numbers of microorganisms are being genetically characterized without culturing them in the laboratory today through ______.

A)mass spectrometry and proteomics
B)polymerase chain reaction
C)column chromatography
D)metagenomic sequencing

Question 48

How are the sulfur cycle and the phosphate cycle interconnected?

A)Phosphate is the nutrient source used by sulfur oxidizers.
B)Sulfite is the nutrient used by phosphate reducers.
C)Sulfate and phosphate react together to produce amino acids for protein production.
D) Phosphate is released from rock and soil by sulfuric acid.

Question 49

Which of the following statements concerning metagenomic sequencing is incorrect?

A)Software aligns sequences and assemble large portions of genomes.
B)The samples are subject to polymerase chain reaction for amplification.
C)The sequences of the amplified fragments are determined by next-generation methods.
D)Proteins are extracted from an environment, fragmented, and adaptors are added.

Question 50

Which microorganism is considered phytoplankton? Cyanobacteria
B)Mycorrhizae
C)Nitrogen fixing bacteria
D)Sulfate reducers

Question 51

Which of the following is true of water-saturated soils?

A)They have a low carbon dioxide content.
B)They contain anaerobes.
C)They have a high oxygen content.
D)They provide gases for soil microbes.

Question 52

The bacterium Thiobacillus secretes sulfuric acid into the environment.

Question 53

You are preparing a garden and want to provide the best environment for your plants.Which of the following would you add to the potting soil?

A)Sulfur oxidizers
B)Coliform bacteria Mycorrhizae inoculant
D)Bacteriophage

Question 54

Plastic marine debris was collected from multiple sites in the ocean and examined with electron microscopy and next-generation sequencing.These techniques revealed microbial communities growing on the plastics.Which of the following statements is correct regarding these communities?

A)The community within the plastic must be very similar to the community in the surrounding ocean waters.
B)These communities are very likely to be pure cultures, as plastics have been synthesized precisely because they are resistant to microbial degradation.
C)There are no bacteriophage that use these microbes as hosts, as viruses are rare in marine ecosystems.
D)At least one member of the community must synthesize an enzyme to degrade the hydrocarbon comprising the plastic.

Question 55

The total amount of water in the hydrologic cycle has been decreasing over the last million years.

Question 56

The mutualistic partnership between plant roots and microbes is ______.

A)basidia
B)lichens
C)mycorrhizae
D)rhizopods
E)hyphae

Question 57

Metagenomic analysis involves DNA sequencing of various samples taken from a particular habitat.

Question 58

Select the statement that explains the usefulness of metagenomic analysis in research today.

A) It evaluates microbial diversity in a habitat.
B) It allows the identification of unculturable microorganisms.
C) It detects the abundance of microorganisms in an environment.
D) All of these are correct statements.

Question 59

Mycorrhizae are the mutualistic relationship between fungi and the roots of certain plants.

Question 60

The zone of soil around roots of plants is called the ______.

A)biosphere
B)lithosphere
C)rhizosphere
D)hydrosphere
E)ionosphere

Question 61

Which of the following types of microbes is most likely to be found in the sediment of Lake Michigan?

A)Mesophiles; temperatures in the hypolimnion support growth in the 4-9°C range
B)Autotrophs; their carbon source is dissolved carbon dioxide
C)Cyanobacteria; seasonal upwelling of nutrients can cause dramatic increases in their numbers
D)Anaerobes; oxygen is least abundant in the sediment layer

Question 62

Consider a deep sea hydrothermal vent.Which of the following statements is incorrect?

A)Its biome is the deep marine biopshere.
B)The vent hosts communities of chemolithotrophic bacteria.
C)The associated chemolithotrophs are primary producers.
D)The vent is a habitat.

Question 63

The breakdown of man-made compounds by decomposers is called ______.

A)saprobism
B)mineralization
C)decomposition
D)parasitism
E)bioremediation

Question 64

Which of the following statements regarding the infection of root hairs by Rhizobium species is incorrect?

A)Nodules begin to form in the roots as both plant and bacterial partners differentiate.
B)Attachment of Rhizobium cells to plant root hair cells induce curling of the root hair.
C)This is a mutualistic relationship between plant and bacteria.
D)The presence of Rhizobium triggers the formation of syncytial cells.

Question 65

Nutrient deficient aquatic ecosystems are called ______.

A)oligotrophic
B)autotrophic
C)hypotrophic
D)epitrophic
E)eutrophic

Question 66

Which of the following statements considering the human body as an ecosystem is incorrect?

A)The skin, the gut, and the nasopharynx are all habitats.
B)The microbes present in dental plaque constitute a community.
C)Lactobacillus acidophilus and Lactobacillus jensenii are populations within the vaginal community.
D)An infection can be considered a habitat's response to an alteration in environmental conditions.

Question 67

Considering the human body as an ecosystem, which of the following statements is incorrect?

A)The human ecosystem lacks an autotrophic niche.
B)The microbiota in the human gut is comprised of heterotrophs.
C)Microbes act as producers, consumers, and decomposers within the human ecosystem.
D)Energy for the human microbiome derives exclusively from the food we eat.

Question 68

The thermocline is broken down by temperature changes that allow upwelling to occur.

Question 69

Looking at the use of antibiotics as growth promoters in livestock through the lens of "One Health," which of the following statements best describes the interrelationship of these components of the biosphere?

A)Choosing a vegetarian lifestyle goes a long way to avoid risks associated with antibiotic-treated livestock.
B)The broad range of antibiotics available will provide widespread protection from pathogenic microbes.
C)Livestock can be more susceptible to infectious diseases because of the energy required for such rapid growth.
D)Spontaneous antibiotic resistance that arises in animals can be rapidly spread to humans who work on factory farms.

Question 70

You are "living off the grid" meaning that you are not using any public utilities: no water supply, sewer connection, natural gas, or electricity.You do have a septic tank, whose pipe carries sewage underground where it is released over a wide area, the leaching field.There is also a small pond out there that you have stocked with fish.However, you notice that the fish are floating dead in the water, and the pond has a green scum on it.What happened?

A)There is oxygen depletion in the pond due to the leakage of phosphates and other compounds from your septic tank.
B)There are not enough nutrients in the water, so the fish died.
C)Chemical toxins from your septic tank cleaner have killed the fish.
D)The fish died due to a lack of calcium, which then caused the algae to overgrow.

Question 71

Using microbes to break down or remove toxic wastes in water and soil is called ______.

A)bioremediation
B)decomposition
C)synergism
D)recycling
E)mineralization

Question 72

Eutrophication

A)restricts the O₂ supply to water below the surface.
B)is characterized by heavy surface algal blooms.
C)occurs when there are excess nutrients in aquatic ecosystems.
D)causes massive die-off of fish and invertebrates.
E)All of the choices are correct.

Question 73

Considering the increase in tick-borne diseases in the context of "One Health," which of the following statements is correct?

A)Borrelia, Babesia, and Ehrlichia can rapidly adapt to changing insect vectors, thereby increasing their populations as they move from ticks to mosquitoes.
B)Ticks carrying multiple pathogens reproduce at a slower rate, rendering them less likely to infect humans.
C) Lyme disease has spread from deer to humans upon increasing development of the forested environments usually inhabited by deer.
D)Ticks carrying Borrelia are likely to encounter hosts already infected with Babesia or Ehrlichia, resulting in ticks that co-infect with multiple pathogens.

Question 74

The three components that interact for one health are

A)the environment, humans, and animals.
B)prokaryotes, eukaryotes, and viruses.
C)producers, consumers, and decomposers.
D)bacteria, archaea, and eukaryotes.

Question 75

Which of the following statements regarding red tides is incorrect?

A)Toxins produced by dinoflagellates are skin irritants.
B)Red tides are also known as harmful algal blooms (HABs).
C)Dinoflagellates produce a toxin that causes paralytic shellfish poisoning.
D)Red tides result from an overgrowth of dinoflagellates.

Question 76

The warmest area of a lake during the summer is the ______.

A)benthic zone
B)limnion
C)thermocline
D)hypolimnion
E)epilimnion