A) dead zone
B) watershed
C) wetland
D) lithosphere
A) A positive feedback loop would stabilize the concentration of a substance.
B) Positive feedback loops are more common in natural systems altered by human actions.
C) Positive feedback loops are relatively common in nature compared to negative feedback loops.
D) A positive feedback loop would reverse a change that may cause damage to an ecosystem.
Use the figure above to answer the following question.
A) the water of the pond is now slightly alkaline
B) the water of the pond is now slightly acid
C) the concentration of hydrogen ion is now lower than at pH 7.5
D) the pond is now pH neutral and it has more hydrogen ions than at pH 7.5
E) there will be no measurable levels of hydrogen ion in the pond
A) Bases
B) Proteins
C) Carbohydrates
D) Lipids
E) Nucleic acids
A) is melting arctic snow exposing dark surfaces that heat up and cause further melting
B) is a thermostat turning on the furnace as the temperature drops
C) are predators eating most of their prey and then declining in numbers
D) is a pond becoming more acidic as a result of pollution
E) are birds migrating south in response to colder temperatures
A) Enzymes
B) Chlorophyll
C) Starch
D) Protein
E) Cellulose
A) ions
B) elements
C) compounds
D) isotopes
E) molecules
A) Inorganic compounds never contain carbon, whereas organic compounds always contain carbon.
B) Inorganic compounds always only consist of two atoms.
C) Organic compounds are always acidic, while inorganic compounds are always basic.
D) Organic compounds consist of carbon atoms joined by covalent bonds and may contain other elements, such as nitrogen, oxygen, sulfur, and phosphorus. Inorganic compounds lack carbon-carbon bonds.
E) A and C are correct.
A) This atom has 8 protons, 6 neutrons, and 8 electrons.
B) This atom has 6 protons, 8 neutrons, and 6 electrons.
C) This atom has 6 protons, 8 neutrons, and 8 electrons.
D) This atom has 6 protons, 6 neutrons, and 6 electrons.
A) No, because as uranium decays, it will shed subatomic particles, not add them.
B) Yes, because the half-life of 235U is 700 million years.
C) No, because neptunium (Np) does not exist.
D) Yes, because 236Pb is a smaller atom than 239Np.
A) Energy provides the ability to change the position, the composition, or the temperature of matter.
B) Energy is the food we eat.
C) Entropy is another name for energy.
D) Energy can be created and destroyed.
A) plant seeds, water, and soil
B) sunlight, plants, and oxygen
C) carbon dioxide, water, and sunlight
D) glucose, oxygen, and sunlight
A) They produce their own inorganic molecules, which can be broken down for energy.
B) Without heterotrophs, there would be no autotrophs.
C) They consume other organisms for energy.
D) They produce their own organic molecules, which can be broken down for energy.
A) wind rotating a turbine
B) a rock rolling down a hill
C) the energy held in bonds between atoms
D) water passing through a hydroelectric dam
A) dead zone
B) ecotone
C) biome
D) ecozone
A) have little vegetation
B) are said to have high primary productivity
C) are usually found in cold, damp climates where decomposition is slow
D) are said to have high secondary productivity
A) Matter unidirectionally flows through an ecosystem, whereas energy cycles within an ecosystem.
B) Energy unidirectionally flows through an ecosystem, whereas matter generally cycles within an ecosystem.
C) Both energy and matter cycle within an ecosystem.
D) Both energy and matter unidirectionally flow through an ecosystem.
A) algal bed; desert
B) open ocean; wetland
C) tundra; coral reef
D) desert; tundra
A) split water molecules and release oxygen in the form of O2
B) break down macromolecules such as starch
C) produce small, high-energy molecules that are used in the Calvin cycle to manufacture sugars
D) defend against predators
E) Both A and C
A) Through the process of digestion, the bugs and bacteria have created new matter that did not exist before.
B) The decomposers are able to use all of the energy that the plant’s leaf obtained from sunlight using photosynthesis.
C) The nutrients from the leaf have been removed from that ecosystem.
D) The nutrients from the leaf have been recycled and released back into the soil.
A) used to predict rainfall and temperature changes in ecosystems
B) helping conservation biologists study habitats and study biodiversity
C) useful in tracking the movements of individual organisms
D) useful in determining the number of heterotrophs in an ecosystem
E) used to measure the economic value of ecosystem services
A) natural sources
B) urban fertilizer runoff
C) municipal and industrial wastewater
D) septic systems
E) agriculture
A) any organism using oxygen for respiration
B) any organism producing biomass directly from photosynthesis
C) heterotrophs only
D) the sum of both living and dead biomass in an ecosystem
E) heterotrophs and autotrophs
A) various species of specialized
B) bacteria
C) mammals
D) pine trees
E) fungi
F) slime molds
A) porous rock formations located underground that store groundwater
B) areas where the water table is above ground most of the year
C) a source of water largely untapped by agriculture and urban systems
D) large bodies of surface water such as lakes and oceans
E) moist areas of soils that permit infiltration of nitrogen and phosphorus
A) increased respiration of the exponentially growing human population
B) mining of limestone (calcium carbonate)
C) use of synthetic fertilizers
D) depletion of aquifers
E) combustion of fossil fuels
A) upgrading stormwater systems to capture runoff from roads and parking lots
B) reducing fertilizer use on farms and lawns
C) planting and maintaining vegetation buffers around ditches and streams that trap nutrient and sediment runoff
D) using artificial wetlands to filter stormwater and farm runoff
E) applying fertilizers to farmland just before heavy rains are predicted
A) magnification
B) evaporation
C) transpiration
D) percolation
E) condensation
The symptoms of the lake suggest ________.
A) pesticide poisoning
B) that all the problems have been created by deforestation
C) eutrophication
D) overfishing
E) the effects of global climate change
A) was within normal limits for an unpolluted lake
B) very low at the surface and normal near the bottom sediments
C) was low-normal on the surface but extremely low near the bottom sediments
D) absent entirely
E) was much higher than normal
A) natural atmospheric phosphorus and nitrogen fixation
B) soil particles eroded from the deforested watershed
C) agricultural and urban fertilizer runoff as well as increased urban wastewater discharges
D) the changes in dissolved oxygen levels
E) the increased algal biomass in the lake
rooted plant life, especially where streams discharged into the lake. The immediate cause(s) of the decline most likely were ________.
A) the fact that the past two winters were colder than usual
B) toxicity of nitrogen and phosphorus to wildlife
C) natural declines in aging wildlife populations
D) pesticide poisoning
E) very low oxygen levels and lack of plants to support animal consumers
A) restoring biodiversity to the deforested areas and closing the wastewater plant
B) closing the wastewater treatment plant and reducing agriculture by 75%
C) reducing fertilizer inputs into the lake by exploring alternative farming techniques, increasing the efficiency of the wastewater plant and using aerators to increase oxygen levels in the areas where streams flow into the lake
D) reducing the population of the town by 50% and agriculture by 50%
E) banning agriculture from the entire region
2) Nutrients promote phytoplankton growth, and increase phytoplankton density in waters.
3) More phytoplankton die and settle where they are metabolized by bacteria.
4) Hypoxic conditions arise in the deep water above the sediments.
5) Aquatic life in and near the sediment flees or suffocates.
2. Increasing air temperatures from global warming speed up the melting of glaciers, exposing darker rocks underneath the ice. The dark surfaces absorb more sunlight, causing further increases in temperature and accelerated glacier melting.
3. A dog pants as it lies in the hot summer sun, releasing excess body heat to the environment and lowering its body temperature to its stable state.
4. A bull on the edge of a herd of cattle panics when it hears a loud noise and begins to run. Five nearby cattle sense the panic and also begin to run. This causes another 15 cattle to panic. Eventually, all 100 cattle in the herd panic and stampede.
5. You invest $1,000 in a savings account and reinvest the 5% interest you earn. The interest makes the amount of money in the account larger, so it earns even more interest. After 20 years, the account contains more than $2,600 and is still growing.
6. When blood sugar levels rise after eating a meal, the pancreas releases the hormone insulin, stimulating cells to take up sugar from the blood. When blood sugar levels drop, the pancreas releases another hormone to stop sugar uptake by cells.
2. positive
3. negative
4. positive
5. positive
6. negative
Consequences:
-death of aquatic organisms that cannot escape
-economic losses for fisheries
-shifts in the marine food web
Solutions:
-policies to promote no-till agriculture
-reduction of fertilizer use to decrease nutrient pollution from farms
-construction of wetlands to absorb nutrients
-composed of long chains of amino acids
-function as enzymes and hormones in organisms
-play a key role in the human immune system
Nucleic Acids:
-function primarily to transmit hereditary information in organisms
-composed of chains of nucleotides
Carbohydrates:
-function primarily as sources of chemical energy, or for energy storage, such as starch
-can be used to build structure, such as cellulose in plant cell walls
-composed of simple sugars or large molecules of chemically bonded simple sugars
a) 1,200 mg/kg soil.
b) 1,900 mg/kg soil.
c) 12 mg/kg soil.
d) 19 mg/kg soil.
a. 2,800
b. 200
c. 2
d. 3,000
a. 3 years
b. 15 years
c. 1 year and 1 month
d. 600,000 years
a. lower, higher
b. higher, lower
c. lower, lower
d. higher, higher
a. 1,000 g zinc.
b. 10,000 mg zinc.
c. 1,000 mg zinc.
d. 10 kg zinc.
-glucose (fuel)
-O2 (gas we inhale)
Outputs:
-CO2 (gas we exhale)
-H2O (water)
-ATP (energy packets that cells use to do work)
Low-relief reef: Treatment
Unrestored bay bottom: Control
1. Reef type is the: Independent variable
2. Adult oyster density is a: dependent variable
3. Spat density is a: dependent variable
A) Sample only the low-relief reefs in each reef complex.
B) Locate the areas of highest oyster density on each of the three reef types and sample only from those locations.
C) Use a random sampling approach to select sites on different reef types from several of the reef complexes.
D) Restrict the sampling to one reef complex only to ensure that factors such as temperature and salinity are consistent.
1. The reef type used in sheltie’s experiment are shown on the ________. The mean density of oysters per square meter is shown on the ________.
2. Adult oysters are represented by ________ , spat are represented by ________ and the total of these groups is represented by ________.
3. What is the total number of oysters growing on high-relief reefs? ____________.
4. What is the average number of oysters per square meter supported on high-relief reefs? ________?
5. How many times greater is the total density of oysters on high relief reefs compared to the total density on low relief reefs? ________?
6. How many times greater is the total density of oysters on high relief reefs compared to the total density on the unrestored bay bottom? ________?
2. yellow bars, blue bars, red bars
3. not shown in graph
4. 1,000
5. 4
6. 170
b. large amounts of dead phytoplankton are decomposed by bacteria
c. the microbial decomposer population increases and consumes more oxygen
d. insufficient oxygen suffocates marine animals, forming a dead zone
e. increased oyster population feeds on increased phytoplankton population
f. the microbial decomposer population remains stable and does not use more oxygen
Drag the labels onto the flowchart to identify the sequence in which carbon moves through these organisms.
2. zooplankton obtain carbon by eating phytoplankton
3. fish obtain carbon by eating zooplankton
4. killer wales obtain carbon by eating fish
5. cellular respiration in organisms returns carbon to ocean and atmosphere
Drag the labels onto the flowchart to identify the sequence in which carbon moves through these organisms
2. a primary consumer eats the plant, the plants carbon enters the primary consumer
3. carbon enters a higher level consumer when it eats the primary consumer, some carbon exists as feces
4. fungi use the carbon that is found in the wolf’s feces
5. cellular respiration in fungi releases carbon dioxide to the atmosphere
Drag each description to the appropriate bin.
– This cycle’s largest reservoir is ocean water.
– Transpiration is a major flux in this cycle.
Carbon Cycle:
– This cycle is significantly affected by the extraction of fossil fuels.
– Photosynthesis is a major flux in this cycle.
Nitrogen Cycle:
– Nitrification is a major flux in this cycle.
– This cycle’s largest reservoir is the atmosphere.
Phosphorus Cycle:
– This cycle is affected by the release of detergents in treated wastewater.
– The weathering of rock is a major flux in this cycle.
What information is presented on the y-axis of the graph?
A) time, measured in 20-year intervals
B) the amount of nitrogen stored in Earth’s ecosystems
C) the amount of nitrogen humans add to Earth’s ecosystems each year
D) the amount of nitrogen added to Earth’s ecosystems each year
What is the natural rate of nitrogen fixation in Earth’s ecosystems?
A) 2020 teragrams of nitrogen per year
B) 2020 kilograms of nitrogen per year
C) 100 kilograms of nitrogen per year
D) 100 teragrams of nitrogen per year
What does the red graph line represent?
A) input of nitrogen from burning fossil fuels
B) input of nitrogen from all human activities
C) input of nitrogen from fertilizer and industrial processes
D) input of nitrogen from legumes grown on farms
In 1960, what was the total amount of nitrogen released by human activities?
A) about 25 kilograms
B) about 50 teragrams
C) about 25 teragrams
D) about 50 kilograms
E) about 270 teragrams
During which period did the total amount of nitrogen released by human activities increase most rapidly?
A) 1920-1940
B) 1940-1960
C) 1960-1980
D) 1980-2000
E) 2000-2020
Which factor was the major contributor to the rapid increase in the total human input of nitrogen between 1960 and 2000?
A) a rapid increase in fertilizer use and industrial processes
B) a rapid increase in the use of fossil fuels
C) a rapid increase in the amount of legumes grown on farms
D) a rapid increase in the natural rate of nitrogen fixation
Is the following statement supported or not supported by the data shown in the graph?
In the year 2000, the total human input of nitrogen into Earth’s ecosystems was almost twice the natural rate of nitrogen fixation.
A) supported
B) not supported
C) cannot be determined from the graph
Is the following statement supported or not supported by the data shown in the graph?
By the year 2100, the increasing use of fertilizer will cause the total human input of nitrogen into Earth’s ecosystems to be about three times the natural rate of nitrogen fixation.
A) supported
B) not supported
C) cannot be determined from the graph