Q&A Hero

Q: Differentiate between an open and a closed system. If possible, give a specific and somewhat detailed example of each. Do both exist in nature? Why or why not?

Q: Compare and contrast positive and negative feedback loops. Give an example of each. Which are more common in natural systems and why?

Q: Denitrifying bacteria convert atmospheric nitrogen gas directly to nitrate ions.

Q: Humans have tremendously accelerated the flux rate of carbon from the earth to the atmosphere by burning fossil fuels.

Q: Producers and primary consumers can take up phosphorus dissolved in water; higher-level consumers must obtain phosphorus from organisms below them in the food web.

Q: Most ecosystems are limited by nitrogen as phosphorus is weathered from rock at relatively high rates.

Q: Excess carbon dioxide in the atmosphere is most easily taken up by producers in photosynthesis and by the ocean.

Q: Biogeochemical cycles are one example of a positive feedback loop.

Q: Ecosystems that convert solar energy to biomass rapidly are said to have low primary productivity.

Q: The secondary consumers obtain their nutrients from ________.A) primary producers and/or detritivores and decomposersB) primary producers onlyC) detritivores and decomposers onlyD) primary and/or tertiary consumersE) tertiary producers and/or detritivores and decomposers

Q: During a year, the gross photosynthesis of grass growing on a 2000 m2 parcel of land was 10 000 kg of carbon (kg C) per year. A farmer harvested this grass to feed it to her animals. The grass contained 1000 kg of carbon. The animals that ate the grass gained 100 kg of carbon in their meat. What was the secondary productivity of this piece of land? A) 5 kgC/m2/yr B) 0.5 kgC/m2/yr C) 0.05 kgC/m2/yr D) 5 kgC/yr E) 0.5 kgC/yr

Q: Human beings have dramatically altered the flux rate of nitrogen from ________. A) the atmosphere to various pools on the Earth's surface B) soils to the atmosphere C) proteins to inorganic ions in soils D) oceans to soils E) producers to consumers through increased wildfires

Q: Which of the major water and nutrients cycles has its largest reservoir in the ocean? A) sulphur B) carbon C) nitrogen D) phosporus E) water

Q: A pond contains 1000 m3 of water. The water flows into the pond at 5 m3 per day, flows out of the pond in form of a stream at 4 m3 per day, and evaporation from the pond's surface is 1 m3 per day. What is the water turnover time in this lake? A) 200 days B) 1000 days C) 250 days D) 100 days E) There is not enough data to answer this question.

Q: By damming rivers and using methods such as flood irrigation, we are ________. A) increasing evaporation B) increasing the water table C) decreasing the water table D) decreasing transpiration E) increasing transportation

Q: Aquifers are ________. A) natural ponds and lakes B) recharge lakes at water quality facilities C) underground water reservoirs D) the result of transpiration E) oceans

Q: The freshwater we depend on for our survival accounts for ________. A) two-thirds of all water on Earth B) one-third of all water on Earth C) 10% of all water on Earth D) 3% of all water on Earth E) less than 1% of all water on Earth

Q: Humans have dramatically altered the rate of nitrogen fixation into forms usable by autotrophs ________. A) by burning fossil fuels to meet our energy needs B) because of the erosion of farmlands through poor agricultural practices C) as we produce synthetic fertilizers and apply them to crops, lawns, and parks D) by using antibiotics to reduce the numbers of denitrifying bacteria E) by selectively removing leguminous plants

Q: Nitrogen fixation is a process that makes nitrogen available to plants by ________. A) photosynthesis B) volcanic eruptions C) heterotrophic bacteria converting ammonium to nitrate D) dissolving in freshwater and in the ocean E) mutualistic and free"‘living bacteria

Q: The origin of all nitrogen in biological tissues is ________. A) volcanic activities B) atmospheric nitrogen gas C) nitrogen weathered from rock D) lightning E) the Haber-Bosch process

Q: The origin of all phosphorus in biological tissues is ________. A) volcanic activity B) atmospheric phosphorus gas C) phosphorus weathered from rock D) phosphorus fixed from air by symbiotic bacteria E) phosphorus from ocean waters

Q: Which of the major water and nutrients cycles has its largest reservoir in the atmosphere? A) sulphur B) carbon C) nitrogen D) phosporus E) water

Q: Plants conduct photosynthesis, making glucose and other carbohydrates. To do this, they need ________. A) water from the soil B) water from the humid atmosphere and carbon dioxide from the soil C) water from the soil and carbon dioxide from the soil D) carbon dioxide from the atmosphere E) water from the soil and carbon dioxide from the atmosphere

Q: Experiments have demonstrated that the growth in the oceans is usually limited by availability of ________. A) iron or nitrogen B) nitrogen C) phosphorus D) iron or phosphorus E) carbon

Q: Macronutrients ________. A) are large molecules necessary for making macromolecules B) are required in large amounts for organisms to survive C) are the only nutrients that can be tracked in nutrient cycles D) can be taken up only by plants from rock cycles E) are what large predators eat

Q: Examining areas from the landscape scale, termed landscape ecology, is useful because ________. A) humans have not yet caused alterations to landscapes B) the dynamics of animals result in localized problems C) the role of ecosystems is often overstated D) multiple ecosystems may exist in a single area with many transitional zones E) it helps to define the entire closed system

Q: Ecotones are the ________. A) sounds that animal communities make in ecosystems B) interactive behaviours leading to communication C) areas between territories of organisms D) studies of specific biomes by ecologists E) transitional zones between ecosystems

Q: The biosphere consists of the ________. A) saltwater and freshwater in surface bodies and the atmosphere B) solid earth beneath our feet (above the mantle) C) all the planet's living organisms D) air surrounding our planet allowing life to exist E) abiotic portions of the environment

Q: The rate at which biomass becomes available to consumers is termed ________. A) gross primary productivity B) ecosystem productivity C) fertility D) secondary production E) net primary productivity

Q: A small section of prairie grasses, over a year, produces enough biomass to feed insects, mice, rabbits, birds, deer, antelope, and a host of decomposers. The amount of food potentially available to the herbivores is the ________. A) net primary production B) gross primary production C) secondary production D) productivity E) food chain

Q: The rainforest of western Vancouver Island where it meets the Pacific Ocean could be called a(n) ________. A) coastal superbiome B) ecotone C) dead zone D) closed ecosystem E) abiotic system

Q: A natural ecosystem, undamaged by human activity, is a(n) ________. A) mostly closed system of organic materials and energy; everything is recycled B) open system of organic materials and an open system of energy, everything is recycled C) mostly closed system of organic and inorganic materials, and an open system of energy D) mostly closed system of organic and inorganic materials, and a closed system of energy; everything is recycled E) open system of inorganic materials, and an open system of energy

Q: The abiotic components of our planet can be divided into the ________. A) geosphere and atmosphere B) lithosphere, hydrosphere, and atmosphere C) lithosphere, biosphere, and atmosphere D) lithosphere, hydrosphere, biosphere, and atmosphere E) centrosphere, geosphere, biosphere, and anthroposphere

Q: The eutrophication that has taken place in the Gulf of St. Lawrence and other locations appears to be due to ________. A) global warming from human use of fossil fuels B) pesticide use along the waterways C) heavy metals dumped in the sewage D) weather alone, because it is only obvious in the summer E) excess nutrients from fertilizers

Q: Cattle on an open range, in some areas, may compact fragile soils while grazing. This can damage plant roots, leading to fewer, smaller plants, which may in turn cause cattle to graze more and work harder to obtain food. This is an example of a ________. A) positive feedback loop B) negative feedback loop C) homeostatic system D) dynamic equilibrium E) food web

Q: A system receiving inputs and producing outputs without undergoing any changes in size or function is said to be in ________. A) static control B) environmental balance C) harmonic resonance D) normal balance E) dynamic equilibrium

Q: Any network of relationships among a group of components, which interact with and influence one another through exchange of matter and/or information, is referred to as ________. A) an interchange B) a system C) an ecosystem D) an environmental collaboration E) a hierarchy

Q: ________, such as soil insects and millipedes, are consumers of nonliving organic matter.

Q: The total biomass that heterotrophs generate by consuming autotrophs is termed ________.

Q: In the process of ________, autotrophs such as green algae and plants use the Sun's energy, water, and carbon dioxide from the air to produce new biomass.

Q: Substances move through the environment in cycles called nutrient cycles or ________ cycles.

Q: Briefly explain what the main difference is between the flow of matter and the flow of energy in an ecosystem.

Q: The term ________ describes all of the interacting organisms and the abiotic factors that occur in a particular place at the same time.

Q: The process of nutrient enrichment, subsequent increased production of organic matter, and eventual ecosystem degradation is known as ________.

Q: The extremely low dissolved oxygen concentrations in the "dead zone" represent a condition called ________.

Q: Define homeostasis.

Q: What is the net effect of human activity on Earth's carbon reservoirs?

Q: What are the anthropogenic sources of phosphorus, and why are they a problem?

Q: The reservoir in which sources are equal to sinks is said to be in ________.

Q: "The missing carbon sink" is likely in ________.

Q: The main reservoir of phosphorus is in ________.

Q: What three factors contribute to the "dead zone" in the waters off the Gulf of Mexico?

Q: Match the following.A) groundwatersB) cryosphereC) biomassD) ecosystemE) lithosphereF) biosphereG) evaporation/precipitationH) mantleI) biomeJ) evaporationK) decomposersL) detritivoresM) river runoffN) transpiration1.The largest flux of water in the hydrological cycle2.Consists of all the planet's living (and recently deceased and decaying) organisms3.Matter contained in living organisms4.The solid earth beneath our feet5.The process by which water moves from lakes or rivers to the atmosphere6.The second largest reservoir of water on Earth7.Describes a category that fungi and bacteria fit into

Q: Refer to Figure 3.1. Overall, it appears that terrestrial biomes with more available freshwater ________.A) tend to have less productivity than those without much freshwaterB) tend to have about the same productivity as those without much freshwaterC) tend to have more productivity than those without much freshwaterD) don't differentiate between freshwater as rainfall and freshwater as ice in glaciersE) No valid conclusions can be drawn.

Q: Refer to Figure 3.1. Overall, it appears that ________. A) some ecosystems are 250 times more productive than others B) cultivated land is more productive than natural ecosystems C) shallow waters are more productive than deep waters D) terrestrial ecosystems have higher productivity than aquatic ones E) no valid conclusions can be drawn

Q: Figure 3.1Use Figure 3.1 to answer the following questions.Refer to Figure 3.1. This graph helps to explain ________.A) why the open ocean is so productiveB) why cultivated lands are a logical choice to replace rainforestsC) why we need to be concerned with damage to rainforests and coral reefsD) why tundra has such high net primary productivity of biomassE) the importance of deserts

Q: Why does burning fossil fuels increase global warming? A) Fossils, if left untouched, cool Earth. B) New energy is created on Earth when fossil fuels are burned. C) Burning fossil fuels destroys the ozone layer. D) Carbon present in coal, oil, and natural gas becomes carbon dioxide when these fuels burn. E) Burning fossil fuels removes water vapour from the atmosphere.

Q: The primary source of increased levels of greenhouse gases on Earth is ________. A) increased photosynthetic activity B) loss of heterotrophs C) modern human lifestyles D) aerosol spray cans E) asteroids falling to Earth

Q: Overpopulation contributes to global warming when ________. A) most of the population is vegetarian B) there is also greater consumption of natural resources C) we compromise our living standards D) most people use public transportation E) solar energy is used as the primary source of energy

Q: Nitrous oxide from burning fossil fuels, in addition to being a greenhouse gas, contributes to acid precipitation. This can be explained by ________. A) its ability to form compounds that raise pH B) its ability to form compounds that lower pH C) the ability of acids to raise the temperature of the substances which dissolve them D) the airborne nature of all compounds containing nitrogen E) the hydrogen bonds connecting the nitrogen and oxygen atoms in the molecule

Q: Read the following scenario and answer the questions below.Almost all environmental scientists agree that gases contribute to global climate change. Carbon dioxide, methane, nitrous oxide, ozone, halocarbons (CFCs and HFCs), and water vapour are the main culprits. These "greenhouse gases" have increased dramatically in our atmosphere in the last 300 years, because of rapid industrialization. Human activities significantly increase greenhouse gases in our atmosphere. Chief among these is the burning of fossil fuels for energy. When we burn fossil fuels, we combine the carbon in fossil remnants of an organic matter with oxygen and release the resulting gasses into the atmosphere. With rising standards of living in developing countries, emissions of carbon dioxide and other greenhouse gases are expected to continue to rise. If unchecked, it is predicted that carbon dioxide levels will reach twice preindustrial levels by mid-century and double again by the end of the century. Computer models have shown that this increase alone could raise Earth's temperatures by 1 to 3C by 2100.The burning of fossil fuels is chemically most similar to which of the following biological processes?A) phytoremediationB) autotrophyC) chemosynthesisD) cellular respirationE) photosynthesis

Q: Describe several properties of water that explain why the lakes in Canada typically do not freeze all the way to the bottom even during extremely long and cold winters.

Q: Explain how isotopes are used in environmental science and provide an example from your text.

Q: Compare the processes of photosynthesis and cellular respiration. Include a brief explanation of autotrophs and heterotrophs in your answer.

Q: Summarize the heterotrophic hypothesis, the extraterrestrial hypothesis, and the chemoautotrophic hypothesis for the development of life on Earth.

Q: Explain why chemistry is important in examining environmental issues and solving environmental problems. Illustrate with examples of such issues/problems.

Q: Describe the first and second laws of thermodynamics. Illustrate both laws by using an example of a burning log of firewood.

Q: List the four types of macromolecules essential to life. Describe the structures of each, and describe their major role(s) in organisms.

Q: Describe the rock cycle, explaining how the three major types of rock form and break down.

Q: Mariana Trench, Earth's deepest abyss, was created at a transform plate boundary.

Q: The Murchison meteorite, which fell in Australia in 1969, was found to contain bacteria.

Q: Bacteria in deep-sea vents use the chemical bond energy in water molecules to transform inorganic compounds into organic compounds in a process called chemosynthesis.

Q: Japan is a product of a continental collision.

Q: All landmasses were once joined together in a supercontinent called Pangaea.

Q: The chemoautotrophic hypothesis is also known as the panspermia hypothesis.

Q: The heterotrophic hypothesis for the origin of life on Earth argues that the first life forms to evolve were heterotrophs living in deep-ocean vents.

Q: List four samples of freshwater of different temperatures in order of increasing density (with the least dense first and the densest last). All temperatures are in C:A) -5 , 20 , 4 , 1B) 20, 4, 1, -5C) 20, 1, 4, -5D) -5, 1, 4, 20E) -5, 20, 1, 4

Q: 14C has 6 protons and ________. A) 8 neutrons B) 8 electrons C) 6 neutrons D) 14 neutrons E) 14 electrons

Q: Which is NOT true about granite? A) It is extrusive rock. B) It is plutonic rock. C) It has a coarse-grained appearance. D) It cooled slowly during its formation. E) It solidified below Earth's surface.

Q: Which is NOT true about basalt? A) It is an intrusive rock. B) It is the principal rock of the Hawaiian volcanic islands. C) It has small crystals. D) It cooled rapidly during its formation. E) It is the main rock of oceanic crust.