Bio exam 4 quiz
What is the total amount of chemical energy produced by photosynthesis or chemosynthesis in a particular ecosystem? net primary production total primary production gross primary production respiration
gross primary production
A researcher has a petri dish containing several species of bacteria, but no viruses. She notices that the population of E. coli in her petri dish has no antibiotic resistance. Two weeks later, she reassesses the bacteria and finds that the E. coli have acquired antibiotic resistance. How could this have happened? E. coli acquired the genes conveying antibiotic resistance through transformation. Spontaneous mutations conveying antibiotic-resistance arose in the E. coli population of the petri dish. E. coli acquired the genes conveying antibiotic resistance through conjugation with other bacterial cells. All of the answer options are correct.
All of the answer options are correct.
Which of the statements below is true regarding the movement of carbon between organisms in a food web, and the transfer of energy between organisms in different trophic levels? (Select all that apply.) Energy can be continuously cycled, but carbon cannot. Both energy and carbon can be continuously cycled. Neither energy nor carbon can be continuously cycled. Carbon can be continuously cycled, but energy cannot. Carbon in the feces of a top predator can be decomposed and used by primary producers in the form of CO2; the energy in the feces is used by the decomposers and is released as heat.
Carbon can be continuously cycled, but energy cannot. Carbon in the feces of a top predator can be decomposed and used by primary producers in the form of CO2; the energy in the feces is used by the decomposers and is released as heat.
In a trophic pyramid, the biomass of lower trophic levels is typically much greater compared to that of higher levels. What does this tell you about the transfer of energy between trophic levels? Select all that apply. Energy is lost as it moves from lower to higher trophic levels. Energy does not move from lower to higher trophic levels. The amount of energy remains the same as it moves between trophic levels. Energy is gained as it moves from lower to higher trophic levels.
Energy is lost as it moves from lower to higher trophic levels.
Most of Earth's primary production comes from tropical rainforests. True False
False
Which is true of Lyme disease? Pick the one, best answer. Lyme disease causes substantially high death rates in black legged tick populations Lyme disease is caused by a virus that infects bats Lyme disease is caused by a type of bacterium that normally lives in deciduous forest communities, but sometimes moves into human populations Lyme disease is a disease of conservation concern, because ticks transfer it among the mice and deer populations in deciduous forests Lyme disease is caused by a eukaryotic parasite that ticks transfer from animal hosts to human hosts
Lyme disease is caused by a type of bacterium that normally lives in deciduous forest communities, but sometimes moves into human populations
Terrestrial autotrophs typically obtain their carbon from: C6H12O6 (glucose). CO2 (carbon dioxide). CH4 (methane). N2 (nitrogen gas). ATP.
O2 (carbon dioxide).
What is a pan-resistant infection? (This is based on the McKenna article.) One that is not responsive to any antibiotics One that is resistant to penicillins and vancomycin, but still sensitive to other antibiotics. One that occurs as a result of a pandemic (that is, a global epidemic)
One that is not responsive to any antibiotics
____________________________ form the base of all terrestrial food webs. Prokaryotes Bacteria Fungi Photosynthetic organisms Decomposers Insects
Photosynthetic organisms
____________ are organisms that derive energy from sunlight. Heterotrophs Phototrophs Chemoautotrophs Chemoheterotrophs
Phototrophs
The organism that causes malaria is in what genus? Candida Plasmodium Streptococcus Enterobacter Clostridium Neisseria
Plasmodium
Which of the following trophic levels contains the most energy? Top predators Secondary consumers Primary consumers Primary producers Tertiary consumers Herbivores
Primary producers
Human introductions of Burmese pythons into the USA has had the effect of reducing population sizes of small mammals in the Everglades National Park in southern Florida. True False
True
True or false: A maple seed is planted and 100 years later it is a 200 foot tall tree. Ignoring water, most of the mass of the maple tree is the result of carbon dioxide used in photosynthetic reactions. True False
True
Antibiotics can kill _____ in the human body, which may sometimes lead to health problems such as inflammatory bowel disease. harmful bacteria beneficial bacteria fungi archaeons both harmful and beneficial bacteria
both harmful and beneficial bacteria
Which of the following things result from symbiotic relationships between bacteria and eukaryotes? (Select all correct choices.) cellulose breakdown in the cow gut bioluminescence in the bobtail squid vitamin production in the human gut amino acid synthesis in aphids
cellulose breakdown in the cow gut bioluminescence in the bobtail squid vitamin production in the human gut amino acid synthesis in aphids
Organisms that derive their energy and carbon from organic compounds are ____________. chemoautotrophs chemoheterotrophs photoheterotrophs photoautotrophs
chemoheterotrophs
Chloroplasts are thought to have evolved from: autotrophic protists. proteobacteria mitochondria. cyanobacteria. algae.
cyanobacteria.
What is the term for the community of organisms and the physical environment that the community occupies? biosphere ecology food web population ecosystem community
ecosystem
"Disease" is the term used for the physical symptoms caused by a parasite or pathogen. false true
true
Which of the following is considered a carbon reservoir? (Select all that apply.) the Great Barrier Reef Redwood National Park the Atlantic Ocean all the organisms on Earth
the Great Barrier Reef Redwood National Park the Atlantic Ocean all the organisms on Earth
Terrestrial photosynthesis uses carbon in ________ from the ______ and energy from ______ to produce _______ that have ________ energy. Glucose; plants; sunlight; organic molecules; heat Carbon dioxide; air; sunlight; organic molecules; chemical potential Carbon dioxide; soil; plants; organic molecules; heat Glucose; soil; glucose; organic molecules; chemical potential
Carbon dioxide; air; sunlight; organic molecules; chemical potential
True or False. The invention of immunizations had no effect on decreasing human deaths due to infectious diseases. True False
False
True or False: As you travel from 90 degrees north latitude south to the equator, you would expect species richness to decrease. True False
False
Viruses compose a fourth, distinct branch on the tree of life. False True
False
Which of the following is an accurate distinction between the nitrogen (N) and carbon (C) cycles? The N cycle has an atmospheric reservoir while the C cycle does not. Carbon cycles and nitrogen flows. Nitrogen cycles and carbon flows. The C cycle is in global balance, but the N cycle is not. None of these choices is an accurate distinction between the C and N cycles. Conversions between different forms of N are accomplished by biotic processes, whereas conversions between forms of C are accomplished by abiotic processes. The C cycle has an atmospheric reservoir while the N cycle does not.
None of these choices is an accurate distinction between the C and N cycles.
Consider the "Climate Change" pre-discussion work Figure 1 (Figure 2.11: Global energy budget under present-day climate conditions). In this figure, the arrows indicate: (Pick one answer.) The change in greenhouse gas concentration in the atmosphere The movement of solar and heat energy through the atmosphere and toward or away from the surface of the earth The cycling of matter through the ecosystems of earth, focusing on water and carbon The heat energy moving out of the earth's atmosphere (in Watts per meter squared) is about half of the solar energy (in Watts per meter squared) moving into the atmosphere, because of the greenhouse effect The flow of energy through ecosystems, focusing on the transfers during trophic interactions
The movement of solar and heat energy through the atmosphere and toward or away from the surface of the earth
True or false? Sunlight is required for plant growth. When light energy is absorbed by a leaf, after a series of chemical reactions, the light energy is transformed into potential energy stored in the glucose molecule. True False
True
Which of the following represents a way that viruses are classified? (Choose all that apply) Whether they use DNA or RNA as their nucleic acid The type of host they infect Whether they are in Domain Archaea or Domain Bacteria Whether they are single or double-stranded
Whether they use DNA or RNA as their nucleic acid The type of host they infect Whether they are single or double-stranded
A disease that has always infected people in one geographic region increases substantially in prevalence and now infects people on five continents. This describes: a zoonosis a pandemic a disease epidemic an endemic disease
a pandemic
True or false: If all other aspects of their lifestyles were equivalent, a vegetarian would have a smaller ecological footprint than someone who consumes a large amount of meat. false true
true
True or false: Plants that have symbioses with nitrogen-fixing bacteria provide these bacteria with food in the form of carbohydrates. true false
true
True or false: Some plant nutrients are more mobile in soil than others. false true
true
How do primary producers directly return CO2 to the atmospheric reservoir (pool)? Gross Primary Productivity Photosynthesis Defecation Cellular respiration Nitrogen fixation Biosynthesis Excretion Uptake Carbon fixation
Cellular respiration
Which of the following statements about the concept of an ecological footprint is FALSE? It encompasses the energy used to produce goods AND the energy used to ship those goods to a store. The total ecological footprint for humanity is likely greater than the actual surface area of Earth. Countries with the largest population sizes have the largest ecological footprints. It is an estimate of how much land is required to provide the resources used by an individual. Undeveloped countries have smaller ecological footprints than developed countries.
Countries with the largest population sizes have the largest ecological footprints.
Which of the following organisms would most likely be first to colonize an area undergoing succession? oak trees large mammals insects mosses small mammals
mosses
Mitochondria are thought to have evolved from: cyanobacteria. chloroplasts. amoeba. proteobacteria. heterotrophic protists.
proteobacteria.
In a national park on the Hawaiian island of Kauai, ant species A competes with ant species B for food, which consists primarily of the seeds of the plants on the island. Due to habitat destruction, there are no natural predators of the ants in this national park. Humans decide to introduce a natural predator, a spider, to the park. This spider eats the ants indiscriminately (no preference for species A or B). Which of the following is a likely INDIRECT effect of the spider introduction? (a) Ant species A will competitively exclude ant species B. (b) The population sizes of both ant species will decline. (c) Fewer seeds will be eaten so plant population sizes will increase. (d) The population size of the spider will decrease. (e) Choices B and C are both likely indirect effects.
(c) Fewer seeds will be eaten so plant population sizes will increase.
Giant sequoia trees (Sequoiadendron giganteum) are among the largest and longest-living organisms on Earth. These trees grow in weight by up to 1000 pounds of wood per year. As these trees are growing, they: incorporate CO2 into their biomass (wood, roots, and leaves). generate some CO2 through cellular respiration. are probably a net sink of CO2. All of the answer choices are correct.
All of the answer choices are correct.
The largest source of nitrogen fixation on earth is accomplished by: Biological nitrogen fixation, accomplished by bacteria (including Rhizobium) and Archaea Burning of fossil fuels that release nitrate and ammonium as a by-product into the atmosphere. Humans that industrially produce nitrogen fertilizer Lightning that can fix nitrogen into ammonium Biological nitrogen fixation, accomplished by unicellular eukaryotes
Biological nitrogen fixation, accomplished by bacteria (including Rhizobium) and Archaea
Clostridium difficile is a bacterium that is often found in low abundance in the gastrointestinal tract of healthy individuals. It is also a common cause of hospital-acquired infections. Most individuals who become ill with C. difficile do so following antibiotic treatment and these C. difficile infections often do not respond to standard antibiotic therpay. This information suggests that: C. difficile is often resistant to the antibiotics used to treat the infection. C. difficile thrives when a diversity of other microbe species are present in the human gut. none of these options are accurate C. difficile is not pathogenic (disease-causing) in humans. C. difficile is not well adapted to the human gastrointestinal tract.
C. difficile is often resistant to the antibiotics used to treat the infection.
Estimates are that more than 35 million people currently live with HIV. Which of the following are ways that people who are alive today and infected with HIV may have acquired the virus? Choose all that apply. Contact with semen of an infected human Consumption of human breast milk from an infected human Water Contact with blood of an SIV-infected chimpanzee Contact with saliva of an infected human Skin Contact Consumption of meat of SIV-infected chimpanzee Contact with blood of infected human Through bite of infected mosquito Contact with vaginal secretions of an infected human
Contact with semen of an infected human Consumption of human breast milk from an infected human Contact with blood of infected human Contact with vaginal secretions of an infected human
Which of the following is true of gross primary production, net primary production and cellular respiration? Choose all valid statements. Read carefully, as there are multiple gross primary production and net primary production questions on this quiz. Plants contribute to net primary production, but plants do not contribute to gross primary production Gross primary production can be measured in terms of mass per unit time per unit area Gross primary production can be measured in terms of energy per unit time per unit area Both animals and plants can contribute to gross primary production, but plants do not contribute to cellular respiration Cellular respiration only happens in the dark, when there is no sunlight to power photosynthesis
Gross primary production can be measured in terms of mass per unit time per unit area Gross primary production can be measured in terms of energy per unit time per unit area
Which of the following could initiate a trophic cascade in a terrestrial community? Introduction of a new plant species that thrives in the location where it is introduced Introduction of a tertiary consumer to a community that previously just had primary and secondary consumers Removal of a primary consumer from the community Removal of a dominant species from the community Introduction of a species who has a mutualistic relationship with an herbivore who already lives in the community
Introduction of a tertiary consumer to a community that previously just had primary and secondary consumers
The individual thin filaments that make up the body of a multicellular fungus are the: fruiting bodies. spores. roots. mycelia. hyphae.
hyphae.
Which of the following provides strong evidence for the endosymbiotic hypothesis? Bacterial genes are more similar (& closely related) to mitochondrial genes than to chloroplast genes Chloroplast genes are more similar (& closely related) to nuclear genes of the host than to mitochondrial genes Chloroplast genes are more similar (& closely related) to mitochondrial genes than to bacterial genes Mitochondrial genes are more similar (& closely related) to bacterial genes than to nuclear genes of the host Nuclear genes are more similar (& closely related) to cyanobacterial genes than to genes from Archaea
Mitochondrial genes are more similar (& closely related) to bacterial genes than to nuclear genes of the host
So-called "dead zones" in coastal oceans are associated with nutrient runoff and oxygen-depleted bottom waters. What causes the oxygen depletion? Nutrient runoff causes the waters to warm, which causes them to lose oxygen. Nutrient runoff enhances population growth of cyanobacteria and algae, which consume oxygen via aerobic respiration. Nutrient runoff enhances population growth of cyanobacteria and algae which, in turn, support the growth of fish populations. Fish consume oxygen via aerobic respiration. Nutrient runoff enhances population growth rates of algae and cyanobacteria. When the phytoplankton cells die, this big pulse of detritus increases population sizes of decomposers which consume oxygen during cellular respiration. Nutrient runoff enhances population growth of algae and cyanobacteria, which consume oxygen via photosynthesis.
Nutrient runoff enhances population growth rates of algae and cyanobacteria. When the phytoplankton cells die, this big pulse of detritus increases population sizes of decomposers which consume oxygen during cellular respiration.
In addition to the protein capsid, what other components make up an HIV virus particle? Choose the most complete and accurate answer. RNA genome and lipid bilayer envelope DNA genome, reverse transcriptase and other viral proteins, lipid bilayer envelope RNA genome, reverse transcriptase and other viral proteins, lipid bilayer envelope DNA genome and lipid bilayer envelope DNA genome, reverse transcriptase and other viral proteins RNA genome, RNA transcriptase and other viral proteins
RNA genome, reverse transcriptase and other viral proteins, lipid bilayer envelope
The hemlock wooly adelgid, Adelges tsugae, (an insect) was introduced into Virginia in a shipment of lumber that came from Asia in the 1950s. This insect feeds exclusively on the sap of hemlock trees, which are gymnosperms. The hemlock wooly adelgid established many populations in Virginia's hemlock forests and has spread north and south to colonize hemlock populations in 18 other US states. If we sequenced the mitochondrial DNA from the hemlock wooly adelgid and constructed a phylogeny, the mitochondrial DNA sequences of the insect would be more similar to the DNA sequences of free living alpha-proteobacteria compared to the nuclear DNA sequences of hemlock wooly adelgids. False True
True
A patient visits a doctor complaining of a stomach infection. The patient insists that he be prescribed enough antibiotics to kill all of the bacteria in his intestines. Why is this a bad idea? (Select all correct choices.) It's not-any bacteria in his intestines will cause the patient to be sick Such an antibiotic treatment could result in a serious Clostridium difficile infection. Many intestinal bacteria are beneficial (they provide vitamins or break down cellulose).
Such an antibiotic treatment could result in a serious Clostridium difficile infection. Many intestinal bacteria are beneficial (they provide vitamins or break down cellulose).
ou are most likely to observe primary succession when you visit an abandoned agricultural field. a desert after a fungal pathogen kills many prickly pear cacti. a burned tropical rain forest. an old riverbed. a very young volcanic island. a temperate forest after a gypsy moth outbreak.
a very young volcanic island.
The first law of thermodynamics states that ____________. energy cannot be created or destroyed energy transfers are 100% efficient only eukaryotic cells can produce ATP
energy cannot be created or destroyed
What is the term that describes excessive growth, of one or more phytoplankton species, caused by an excess of nutrient fertilizers? eutrophication productivity oligotrophication secondary productivity sedimentation
eutrophication
True or false: all currently emerging infectious diseases are caused by viruses. true false
false
True or false? Malaria is a disease that has only recently begun infecting humans (within the past 200 years) false true
false
Eukaryotic cells with chloroplasts arose from an ancient symbiosis between: aerobic and anaerobic bacteria heterotrophic eukaryotes and cyanobacteria aerobic bacteria and anaerobic archaea autotrophic bacteria and aerobic archaea primitive protists and cyanobacteria
heterotrophic eukaryotes and cyanobacteria
The highest rates of primary production in the oceans happen ____, while the highest rates of primary production on land happen______. in the middle of the ocean; in areas around the equator only in tropical areas; mostly in tropical areas at the bottom of the ocean where the nutrients are found; at 30 degrees north and south latitude, where it is very warm and there is a lot of sunlight in the ocean around Antarctica; in evergreen forests at 50-70 degrees north latitude in coastal areas; in areas around the equator
in coastal areas; in areas around the equator
The "Anthropocene Period": refers to the period when the earliest primate ancestors appeared in the fossil record. refers specifically to the period of time following the extinction of the dinosaurs. is so named to reflect increasing global surface temperatures. is Latin for "modern era." is a new proposed named to reflect the impact of humans on the planet.
is a new proposed named to reflect the impact of humans on the planet.
Some bacteria in the human intestine aid in the digestion and absorption of nutrients, while utilizing these nutrients themselves as well. This is an example of: mutualism. predation. commensalism. an antagonistic interaction. parasitism.
mutualism.
Which of the following does not contribute to the formation of dead zones? eutrophication fertilizers from agricultural runoff decomposition ocean acidification low oxygen levels
ocean acidification
An organism that acquires energy from the sun and uses C6H12O6 (glucose) as a carbon source would be classified as a: chemoheterotroph. photoheterotroph. chemoautotroph. photoautotroph.
photoheterotroph.
Which of the following terms is used to indicate an organism that eats organisms that create organic molecules using energy captured from the sun? decomposer dominant species primary consumer keystone species primary producer
primary consumer
In a food web, which of the following organisms would be considered heterotrophs? Select all that apply. primary consumers tertiary consumers secondary consumers decomposers primary producers
primary consumers tertiary consumers secondary consumers decomposers
In a pond, tadpoles eat algae and fish eat the tadpoles. Above the pond, grasshoppers eat grass and, at night, are preyed upon by bats. Other bats eat the fish that eat the tadpoles. In this community, the tadpoles are: primary producers. secondary consumers. tertiary consumers. detritivores. primary consumers.
primary consumers.
The broadest level in a trophic pyramid is the level composed of: primary consumers. secondary consumers. tertiary consumers. primary producers.
primary producers.
Which of the following correctly describes a type of viral genome? (Choose all that apply) single-stranded RNA double-stranded DNA double-stranded RNA single-stranded DNA a double helix with one DNA strand and one RNA strand
single-stranded RNA double-stranded DNA double-stranded RNA single-stranded DNA
Recall the classic experiments that Charles Keeling performed at Mauna Loa (Figure 25.1, page 511). What did Keeling's research reveal about atmospheric CO2 levels? that atmospheric CO2 levels fluctuate seasonally All of the answers options are correct. that atmospheric CO2 levels remain constant throughout the seasons that atmospheric CO2 levels are lowest during the spring that atmospheric CO2 levels have decreased over the last 50 years
that atmospheric CO2 levels fluctuate seasonally
Primary producers are the basis for all aquatic and terrestrial food webs. How does the amount of primary production affect community structure? the more energy available from primary producers, the more species that could be supported at higher trophic levels in the community the more energy available from primary producers, the more individuals that could be supported at higher trophic levels in the community Primary production has no direct relationship to community structure
the more energy available from primary producers, the more individuals that could be supported at higher trophic levels in the community
Disturbances and succession both influence the assemblages of species that we see in a particular habitat. true false
true
The genes in chloroplasts more closely match the genes found in cyanobacteria compared to the genes found in the nuclei of photosynthetic eukaryotes. true false
true
The human microbiome is influenced by both genetics and the environment. false true
true
True or false. Fungi are the most important decomposers of wood in forest ecosystems. true false
true
Viral diseases of humans are difficult to treat with drugs because.... viral replication primarily involves human enzymes so it is difficult to make a non-toxic drug that blocks viral replication. viral particles spontaneously self-assemble and cannot be stopped by any pharmaceuticals. we cannot make chemicals to attack viral replication, transcription, and translation enzymes because they are so different from the eukaryotic enzymes. viruses are too small to be acted upon by drugs. All of the choices are correct.
viral replication primarily involves human enzymes so it is difficult to make a non-toxic drug that blocks viral replication.
What is the best way to slow climate change? Adding iron to the oceans to increase photosynthesis There is no way to slow climate change Reducing greenhouse gas emissions Deploy large mirrors along the equator to reflect the most intense rays of the sun back away from the earth
Reducing greenhouse gas emissions
A cell in which viral reproduction occurs is called a: sex cell. somatic cell. daughter cell. host cell. None of the answer options is correct.
host cell.
If phosphorus concentrations were to suddenly increase in a freshwater ecosystem, which of the following would likely occur in the short term? no change in the rate of primary productivity decreased primary productivity increased primary productivity
increased primary productivity
What is the ultimate source of energy for most ecosystems? autotrophs the sun heterotrophs lightning the Earth's molten core
the sun
What do trophic pyramids show? that life on Earth is fragile the relative importance of different organisms in a food web the transfer of energy through an ecosystem the trophic interactions between species in a food web
the transfer of energy through an ecosystem
Viruses are grouped into broad categories according to: their type of genome. the evolutionary relatedness. the type of organism they infect. their particle size. None of the other answer options is correct.
their type of genome.
In what biome would you expect to find the greatest diversity of insects? tropical rain forest desert deciduous forest savanna tundra
tropical rain forest
An unexpected frost in late April killed many different flowers and insects, with rare species and common species both suffering large population declines. This is an example of an ecological disturbance. false true
true
If we reach a post-antibiotic era, which of the following could lead to an individual dying? (Choose all that apply. This is based on the McKenna article.) Cesarean section a scratch bone marrow transplants strep throat an insect bite hip replacements kidney dialysis open-heart surgery
Cesarean section a scratch bone marrow transplants strep throat an insect bite hip replacements kidney dialysis open-heart surgery
Consider figure 25.6 (pages 516-517) in How Life Works (Movement of carbon between reservoirs). How does this figure relate to the greenhouse effect? Pick one answer. The arrows indicate that human actions have unbalanced the flux of water vapor to and from the atmosphere, such that the net flux is now adding water vapor, a greenhouse gas, to the atmosphere. The arrows indicate that the heat moving into the atmosphere is more than the heat moving out of the atmosphere, and this is causing the earth to warm. The arrows indicate that human fossil fuel use and land use change have unbalanced the flux of carbon to and from the atmosphere, such that the net flux is now adding carbon to the atmosphere. The arrows show that the movement of solar energy through the atmosphere and into a sedimentary reservoir is decreasing, and this is causing the earth to warm. The arrows indicate that all the greenhouse gases in the atmosphere have increased since the beginning of the industrial revolution.
The arrows indicate that human fossil fuel use and land use change have unbalanced the flux of carbon to and from the atmosphere, such that the net flux is now adding carbon to the atmosphere.
Trypanosomiasis is a disease found in Africa and is spread by tsetse flies. The disease is caused by Trypanosoma brucei gambiense, which is a protist parasite, and it is usually fatal without treatment. The protist cannot complete its life cycle in the tsetse fly alone; it requires a human host. Humans are the main infected animal, but this pathogen can be found in cattle and pigs. The disease is mostly transmitted by tsetse flies, but can also be transmitted from a mother to an unborn baby, through sexual contact, and by blood transfusions. Based on this information, Trypanosomiasis can be classified as... a global pandemic a vector-borne disease a chronic condition an emerging infectious disease a bacterial disease a disease with a higher Ro than an airborne disease, like the flu a disease without an animal reservoir
a vector-borne disease
From what you know about the global nitrogen cycle, what is one major way that humans alter this cycle? by reducing the fixation of nitrogen by Rhizobium bacteria by reducing the nitrogen available to terrestrial ecosystems by preventing the decomposition of organic nitrogen into ammonium by making nitrogen fertilizers and applying them to large areas by changing rates of nitrogen loss to the atmosphere
by making nitrogen fertilizers and applying them to large areas
In a researcher's lab in the EEB department at UM, they expose small crustaceans to infectious diseases. An undergrad working in this lab put 3 infected hosts in a beaker with 15 uninfected hosts. 6 of the uninfected hosts became infected. What is Ro for this disease? 2 0.5 15 6 3
2
In any given year, approximately how many people are infected with malaria? 1 billion 50 million 10 million 1 million 100 million 5 billion 500 million
500 million
What are the consequences of increasing agriculture to feed a growing human population? All of the answer options are correct. loss of biodiversity through conversion of forests and grasslands to agricultural fields eutrophication and dead zones resulting from increased use of fertilizers greater input of carbon dioxide into the atmosphere through the burning of fossil fuels decreased biological storage of carbon through deforestation
All of the answer options are correct.
What is true of an indirect effect in community ecology? The organisms in this question are those in the "Of Mice and Mast" article that you read for pre-discussion. In "Of Mice and Mast," the authors refer to "indirect interactions;" these lead to indirect effects. The increase in tick prevalence with oak tree mast is an example of an indirect effect. An indirect effect is when a species (A) affects another species (B), and that species (B) affects another species (C), such that species A affects species C through the B-C relationship. The positive correlation between tick prevalence and oak tree mast is an example of an indirect effect. The increase in Lyme disease risk to humans following an oak mast is an example of an indirect effect. All of these choices are true of an indirect effect in community ecology.
All of these choices are true of an indirect effect in community ecology.
There is a giant sequoia (Sequoiadendron giganteum) named Washington (after George Washington) that was believed to be the second largest tree in the world (253.7 ft in height!) until it was struck by lightning in 2003. The lightning strike caused a fire at the top of the tree that reduced Washington's height to about 229 feet. What could have happened to the carbon released during the fire? CO2 was taken up by an archaeon living in the soil and transformed into phosphate CO2 was taken up by a nearby tree, used in photosynthesis to produce a carbohydrate and sequestered (stored) in the biomass of the tree for a hundred years CO2 entered the soil and was transformed to ammonium by decomposers sugars released during the fire were used by fungi to produce ammonium CO2 was released into the atmosphere, thereby reducing the atmospheric pool of carbon
CO2 was taken up by a nearby tree, used in photosynthesis to produce a carbohydrate and sequestered (stored) in the biomass of the tree for a hundred years
Cellular respiration produces ______ from ________. Organic molecules are a source of ______ energy that cellular respiration transfers into _____ and transforms into _____. Carbon dioxide and water; oxygen and sunlight; kinetic; usable chemical energy in the form of glucose; heat energy that the cell can use to do work Glucose and oxygen; carbon dioxide and water; chemical potential; usable chemical energy in the form of ATP; heat energy that cannot do work Carbon dioxide and water; organic molecules and oxygen; chemical potential; usable chemical energy in the form of ATP; heat energy that cannot do work
Carbon dioxide and water; organic molecules and oxygen; chemical potential; usable chemical energy in the form of ATP; heat energy that cannot do work
A new virus (MakeBelieveVirus, MBV) has been discovered which attacks the immune system by targeting macrophages (a type of white blood cell). The MBV has a single-stranded DNA genome. Within host cells, the MBV genome is replicated with viral DNA polymerase. The virus is enclosed in a lipid envelope which contains the genome as well as the enzymes protease and integrase (which incorporates the MBV genome into the host genome). A doctor suspects this is a new strain of HIV. Why might you disagree with the doctor? HIV attacks the respiratory system while MBV attacks the immune system. HIV requires RNA polymerase to incorporate its genome into its host, not for replication of its genome. HIV is not enclosed by a lipid envelope like MBV. HIV does not have a genome made of DNA. HIV does not have a high mutation rate, so it is unlikely doctors would encounter a new strain.
HIV does not have a genome made of DNA.
Which of the following is NOT a hypothesized effect of direct or indirect interactions with mice and other small rodents in the "Of Mice and Mast" article? Mice produce more offspring when there are more available acorns. Tick prevalence increases as mice prevalence increases. Humans make more use of oak forests during masts, because they hunt the deer that move into those forests during mast events. Tick prevalence increases in oak forests during mast events. The prevalence of the Lyme disease bacteria (Borrelia burgdorferi) is greater in oak forests during a mast.
Humans make more use of oak forests during masts, because they hunt the deer that move into those forests during mast events.
Why is the flux of carbon into and out of the atmosphere imbalanced, such that there is a net flux of carbon into the atmosphere at this time? See figures 25.6 (pages 516-517) and 25.8 (page 518). Choose all relevant answers. The amount of solar energy entering the outer atmosphere is greater than that leaving the outer atmosphere. Humans move carbon from sedimentary reservoirs into the atmosphere at a rate that is an order of magnitude (~10 times) greater than natural rates of this movement due to volcanoes and natural oxidation of coal; this leads to a net imbalance in the fluxes into and out of the atmosphere. Although natural fluxes are mostly balanced, human activities cause a net flux of carbon into the atmosphere. Uncertainty in our measurements of natural fluxes causes a slight difference in the net fluxes into and out of the atmosphere.
Humans move carbon from sedimentary reservoirs into the atmosphere at a rate that is an order of magnitude (~10 times) greater than natural rates of this movement due to volcanoes and natural oxidation of coal; this leads to a net imbalance in the fluxes into and out of the atmosphere. Although natural fluxes are mostly balanced, human activities cause a net flux of carbon into the atmosphere.
According to Ostfeld, et al. in the "Of Mice and Mast" article, why is it important to understand how indirect effects structure and affect communities of organisms? Note: In "Of Mice and Mast," the authors refer to "indirect interactions"; these lead to indirect effects. If you do not consider indirect effects, your predictions for biological communities will likely be wrong; this will make you unable to predict the effects of human disturbance on those communities. None of these statements matches what Ostfeld, et al. said about indirect effects. Lyme disease is a major threat to life in all global biomes, and indirect effects are required for predicting outbreaks. Considering direct effects is sufficient for making the most accurate predictions about how communities function, but considering indirect effects paints a richer picture of the community. Historically in community ecology (prior to the 1990s), indirect effects have been the primary focus of research, because they are more important than direct effects.
If you do not consider indirect effects, your predictions for biological communities will likely be wrong; this will make you unable to predict the effects of human disturbance on those communities.
In the Ostfeld, et al. article, "Of Mice and Mast," which of the following is a valid interpretation of figure 1 (page 324)? (Hint: Read the caption carefully.) Every arrow moves from the prey to the predator OR from the plant to the herbivore. "Mast production" refers to the huge increase in population of the mice, ticks, and deer, which are the second level of this food web. Plus symbols (+) can indicate either an increase in biomass OR an increase in density, which could be caused by behavioral changes & migration OR changes in reproductive fitness. The figure indicates that humans eat deer and acorns, but not ticks. The shadowed boxes indicate indirect effects, while the un-shadowed boxes indicate a direct effects. The article presents data which support every arrow in this figure.
Plus symbols (+) can indicate either an increase in biomass OR an increase in density, which could be caused by behavioral changes & migration OR changes in reproductive fitness.
Primary producers are present in every biome, including the deep sea. How can there be primary producers in the deep sea when sunlight does not penetrate to these depths? Primary producers in the deep sea use energy from chemical reactions to drive the production of organic compounds from CO2. Primary producers in the deep sea are chemoheterotrophs. There are probably only two trophic levels in the deep sea because there is only light available from bioluminescent (glowing) organisms. The higher trophic levels (secondary or tertiary consumers) are probably only represented by one or two species because of the low levels of energy available from primary producers.
Primary producers in the deep sea use energy from chemical reactions to drive the production of organic compounds from CO2.
In the early 2000s, there were thick kelp forests in the Pacific Ocean. Kelp is a photosynthetic brown algae that can grow very tall and thick, and is used as food by herbivores such as sea urchins and as a habitat by many species. In 2013-2015, a toxic algal bloom, unusually warm waters, and the outbreak of a new disease killed many starfish and created unfavorable conditions for kelp. As a result, kelp forests are 93% smaller now than they were in 2006. Sea urchins eat kelp, and sea otters eat sea urchins. Sea otters are preyed upon by killer whales (orcas). If killer whales move away from this coastal area because of the reduced kelp forests, what do you expect will occur soon after the whales leave? Sea otter populations will increase, causing a decrease in urchin populations, which may allow kelp forests to recover. Sea otters will have an indirect positive effect on sea urchins, which will further decrease kelp forests. Sea otter populations will decrease, causing an increase in urchin populations, which will result in additional destruction of the remaining kelp forests.
Sea otter populations will increase, causing a decrease in urchin populations, which may allow kelp forests to recover.
Which of the following statements regarding the endosymbiosis theory is TRUE? Chloroplasts and mitochondria used to have smaller genomes when they were free-living organisms, but now need more genes in order to carry out tasks for their eukaryotic hosts. Strong evidence in support of the theory is that the DNA sequences of chloroplasts and mitochondria is very similar to DNA sequences from two different groups of bacteria. There can sometimes be transfer of genes between closely related species. The endosymbiosis theory tells us how the eukaryotic cell first arose. Cyanobacteria arose when a chloroplast was lost from a primitive eukaryote due to a mistake in cell division.
Strong evidence in support of the theory is that the DNA sequences of chloroplasts and mitochondria is very similar to DNA sequences from two different groups of bacteria.