bio 101
Discuss the global conveyor belt of ocean currents and how changes in climate may disrupt it.
Most carbon in the ocean is dissolved carbonate and bicarbonate Ocean currents carry dissolved carbon
Explain why each successive trophic level has smaller biomass as nutrients and energy move up the food web.
Primary producers trapped about 1.2 percent of the solar energy that entered the ecosystem 6-16% passed on to next level
How many species are currently recognized on the planet Earth and how does that compare to the predicted number of species?
1.438,769 described, 10,960,000 predicted
Explain how the stability of biological diversity can be measured
1.Resistance = The ability of an ecosystem to remain in equilibrium despite disturbances 2. 2.Resilience = The speed at which an ecosystem recovers after a disturbance.
Compare a food chain and a food web, explaining which most accurately reflects the actual world and why.
A straight-line sequence of who eats whom Simple food chains are rare in nature Food webs typically show better trophic relationships than chains
Define "biological magnification" and explain why we should limit our intake of fish from the Willamette river.
A nondegradable or slowly degradable substance becomes more and more concentrated in the tissues of organisms at higher trophic levels of a food web. Chemicals that are biologically magnified are not readily broken down by decomposers and tend to be stored in animal tissues.
What did the Hubbard and Brooks experiment show us about deforestation and the effects on water quantity and quality in adjacent watersheds?
A watershed was experimentally stripped of vegetation All surface water draining from watershed was measured Removal of vegetation caused a six-fold increase in the calcium content of the runoff water
List three sources of carbon dioxide in the atmosphere.
Aerobic respiration, volcanic action, burning fossil fuels
Define and discuss tropical rainforests and list several ways that humans are impacting them.
Agriculture can degrade soils quickly Nutrients are eroded away by heavy rains Exposed soils bake and become impenetrable Rain forests cut for lumber and burned for ranching and farming is occurring at alarming rates Researchers estimate that 25% of the carbon released into the atmosphere comes from cutting and burning tropical rain forests, exacerbating global warming Destruction of rain forests is estimated at 50,000 square miles/year—10 times the area of Connecticut Over 50% of the world's rain forests are already gone This destruction is important because a great deal of the Earth's remaining biodiversity occurs in this biome
Why is important to weigh the pros and cons of ecosystem degradation when determining the values of crops and/or development?
All agricultural crops have an origin from wild varieties. Agricultural crops have been selectively bred to produce larger crops with little regard to disease resistance. Wild ancestors of current crops give agricultural producers a source of genes to rely on to cross pollinate current crops. These wild varieties often have genes that convey pest resistance or other important characteristics that can improve the crop or make the crop immune to disease. If biodiversity is lost then these important genes that allow crops to be improved could be lost forever.
Explain how the loss of biodiversity can negatively affect agricultural crops.
All agricultural crops have an origin from wild varieties. Agricultural crops have been selectively bred to produce larger crops with little regard to disease resistance. Wild ancestors of current crops give agricultural producers a source of genes to rely on to cross pollinate current crops. These wild varieties often have genes that convey pest resistance or other important characteristics that can improve the crop or make the crop immune to disease. If biodiversity is lost then these important genes that allow crops to be improved could be lost forever.
Define the term "trophic level".
All the organisms at a trophic level are the same number of steps away from the energy input into the system Producers are closest to the energy input and are the first trophic level
List five different soil characteristics that control how well plants grow.
Amount of humus (organic material) pH (acidity or alkalinity) Degree of aeration (air spaces) Ability to hold or drain water(organics hold water and minerals drain) Mineral content (inorganic material)
Define "ecosystem".
An association of organisms and their physical environment, interconnected by ongoing flow of energy and a cycling of materials
Compare arctic and alpine tundra and list several ways that humans are impacting them.
Arctic: Occurs at high latitudes Permafrost lies beneath surface Nutrient cycling is very slow Alpine: Occurs at high elevations No underlying permafrost Plants are low cushions or mats as in Arctic tundra
Describe the rain shadow effect and list two places we may encounter it in Oregon.
As winds cross a coastal mountain range, they rise and release their moisture on the windward side of the mountain (as air rises, it becomes colder and as such, the water vapor in that air coalesces and falls as rain).Gorge, sisters
Explain the mechanisms in which nutrients are cycled through the environment and energy is lost to it.
At each trophic level, the bulk of the energy received from the previous level is used in metabolism This energy is released as heat energy and lost to the ecosystem Eventually all energy is released as heat
Where does the energy lost in a food web go?
At each trophic level, the bulk of the energy received from the previous level is used in metabolism This energy is released as heat energy and lost to the ecosystem Eventually all energy is released as heat
Define and discuss temperate deciduous forests and list several ways that humans are impacting them.
At their eastern edge, the North American grasslands merge into the temperate deciduous forest biome; this biome is also found in Europe and eastern Asia Annual rainfall averages 30-60 inches, much of which occurs in summer There is enough soil moisture for trees to grow, shading out grasses During freezes in winter, liquid water is unavailable, so the trees shed leaves to conserve water and remain dormant through the winter
Define climate and list four things that affect it.
Average weather condition in a region Affected by: amount of incoming solar radiation prevailing winds elevation precipitation
Define ammonification & nitrification and list one species that performs each function.
Bacteria and fungi carry out ammonification conversion of nitrogenous wastes to ammonia Nitrifying bacteria convert ammonium to nitrites and nitrates Process is termed nitrification.
List the three domains and the six kingdoms of the current classification system.
Bacteria, Archaea, Eukarya. Plants, Animals, Protists, Fungi, Archaebacteria, Eubacteria
Discuss how Streams and rivers collect and transport surface water and list several ways that humans are impacting them.
Begin as springs or seeps Carry nutrients downstream Solute concentrations influenced by streambed composition and human activities
Define and discuss the open ocean explaining the basis of its food web and list several ways that humans impact them.
Beyond the costal regions lie vast areas of ocean where the bottom is too deep to allow plants to anchor and still receive enough light to grow Most open ocean life is restricted to the upper photic zone These organisms are pelagic—free-swimming or floating The food chain in the open ocean is dependent on microscopic phytoplankton, which feed zooplankton, which in turn feed invertebrates, fish, and humpback whales
Define "biocapacity".
Biocapacity estimates the sustainable resources and waste-absorbing capacity of Earth
Discuss the patterns of diversity on planet Earth and explain where the most diversity is located.
Biodiversity is not equally distributed on the planet Earth ▪Some places have an abundance of species, such as lake Victoria in Africa which had at least 500 different species of cichlid fish. Other lakes such as lake Huron in North America only has 79 species of fish. ▪The fish in lake Victoria are only found there (they are endemic) and the fish in lake Huron are found in many rivers and streams. ▪Lake Victoria is at least 15,000 years old and lake Huron is 7,000 years old. ▪Lake Victoria is in a tropical region and lake Huron is in a temperate region. ▪Biologists believe that the age of an area and its location in relation to the equator (latitude) are two factors that explain the differences in biodiversity on Earth.
Define the term "coral bleaching" and explain why it is a problem to marine species.
Bleaching refers to the loss of colour in symbioses between dinoflagellate algae of the genus Symbiodinium and marine benthic animals, e.g. corals. Bleaching generally results in depressed growth and increased mortality, and it can be considered as a deleterious physiological response or ailment.
Describe the wind patterns at any large body of water in the morning and in the afternoon.
Breeze blows in direction of warmer region Direction varies with time of day
How did New York City deal with the degraded water quality it was experiencing and what were their options?
Build a 6-8-Billion-dollar treatment plant with annual cost of 300 million or buy lands surrounding the watershed and restore the ecosystem there for approximately 1.5 billion
Explain how the overloading of the sulfur and nitrogen exchange pools are leading to pollution and acid deposition.
Burning fossil fuels combines nitrogen and sulfur with oxygen creating nitrogen oxides and sulfur oxides. 60 % of all nitrogen oxides and 75% of all sulfur dioxide is produced by burning fossil fuels. This causes acid deposition (acid rain)
List four greenhouse gasses and their sources.
CFCs - synthetic gases used in plastics and in refrigeration Methane - produced by termites and bacteria Nitrous oxide - released by bacteria, fertilizers, and animal wastes Water Vapor - accumulates in the atmosphere due to evaporation, respiration and transpiration.
Define the term "autotroph" and provide three examples from campus
Capture sunlight or chemical energy Producers algae, fungi, kelp
Discuss the carbon cycle listing its reservoir and exchange pools.
Carbon moves through the atmosphere and food webs on its way to and from the ocean, sediments, and rocks Sediments and rocks are the main reservoir (in tropical rain forests living biomass may be main reservoir)
Explain the concept of chemical diversity and why it is important for humans to preserve chemical diversity.
Chemical diversity - species with different genetic characteristics produce different chemicals and different products of metabolism. The different molecules produced include proteins and products and by-products of metabolism. Many of these molecules could be a source of new medicines and products. The loss of biodiversity may eliminate these products before we even discover the species that produce them. Many plants produce secondary plant compounds which are molecules that protect the plant from insects, bacteria, fungus, or other plants. These compounds are the basis of many human medicines.
How do clades organize systematically the relationship of organisms
Clades can be arranged in a hierarchy, with smaller clades nested within larger ones
Compare and contrast conservation and preservation
Conservation: managing resources so that they are available to the most people for the longest amount of time. Preservation: Leaving ecosystems alone without exploiting their resources.
Discuss the differences between convergent evolution (analogous structures) and divergent evolution (homologous structures).
Convergent evolution shows how species have evolved separately but have similar(analogous) structures. Divergent evolution demonstrates how species can have common (homologous) anatomical structures which have evolved for differentpurposes.
Define and discuss coral reefs and list several ways that humans are impacting them.
Coral reefs are complex formations that have accumulated over thousands of years from the calcium carbonate skeletons of corals (relatives of sea anemones) Coral reefs are most abundant in the tropical waters of the Pacific and Indian Oceans, the Caribbean, and the Gulf of Mexico Their maximum water temperatures are between 72-82º F
What is the current rate of extinction compared to the background rate?
Current extinction rates are 500 - 1000 times higher than background extinction rates
Compare detritivores and decomposers.
Decomposers like bacteria and fungi don't eat their food, they decompose it externally. Also, decomposers consume nutrients on a molecular level while detritivores eat large amount of decaying material and excrete nutrients.
Define denitrification, where it occurs and why this is an important way of reducing nitrates from surface waters.
Denitrification is the process that converts nitrate to nitrogen gas, thus removing bioavailable nitrogen and returning it to the atmosphere. Denitrifying bacteria convert nitrates and nitrites to nitrogen gas
Discuss which soil types occur in each biome.
Desert: Horizon O,A,B,C Grassland: A,B Tropical Rain Forest: O, A-E, B Coniferous: O,A,B Deciduous: O,A,B,C
List and explain several issues associated with acid deposition.
Disrupts ecosystems by changing the pH. Damages Forests by weakening immune capacity Destroys all life in some lakes Increases the ability of organisms to absorb toxins Kills decomposer organisms Regulations that limit the amount of nitrogen and sulfur in fossils fuels and coal have decreased the problem but more needs to be done in the future
List the levels of classification from least specific to most specific
Domain Kingdom Phylum Class Order Family Genus Species
Describe the relationship between latitude and altitude and how they effect temperature
Each biome has a particular mix of plants and animals adapted to living under certain environmental conditions.
Discuss why ecosystem restoration has become important in recent years.
Ecosystem Restoration is the "process of assisting the recovery of an ecosystemthat has been degraded, damaged or destroyed" In all cases ecological restoration will improve the biological diversity on degraded landscapes, increase the populations and distribution of rare and threatened species, enhance landscape connectivity, increase the availability of environmental goods and services, and contribute to the improvement of human well-being
Compare ENSO and La Nina climatic events.
El Nino Southern Oscillation Climactic event that involves changes in sea surface temperature and air circulation patterns in the equatorial Pacific Ocean La Nina: Warm water and heavy rainfall move west across the Pacific Warm moist air rises in the western Pacific causing storms Upwelling of cool water along western coasts
Explain where energy comes from and how it is used by organisms.
Energy is constantly replenished and is ultimately derived from sunlight. Energy is converted into a usable source for living organisms (sugars) by organisms capable of photosynthesis. Ultimately the energy used by organisms is lost to the environment in the form of heat which is radiated back into space. All life on earth is supported by a fraction (only 0.03%) of the energy that arrives on Earth.
Describe three different forest biomes and list the type of trees associated with each.
Evergreen broadleaves in tropical latitudes Deciduous broadleaves in most temperate latitudes Evergreen conifers at high temperate elevations and at high latitudes
Define the term "invasive species" and list three problems associated with invasive species.
Exotic species are species that have been intentionally or unintentionally introduced to an area. Some exotic species can overpopulate in the new ecosystems they have been introduced causing them to be considered an invasive species. Invasive species can disturb the new community in ways that persist despite the attempts to remove or control them. The brown tree snake was unintentionally introduced to the island of Guam and has caused at least three species of birds and three to five species of reptiles to go extinct. Many aquatic species have been introduced by ships releasing their ballast in foreign ports. These introductions include the Zebra mussel that has caused wide spread economic and biodiversity losses in the great lakes of North America.
Define the term "heterotroph" and provide three examples from campus.
Extract energy from other organisms or organic wastes Consumers, decomposers, detritivores dogs, birds, humans
How do ecosystems help to stabilize climate on Earth?
GHGAny gas that absorbs infrared radiation in the atmosphere. ... Sequestering atmospheric CO2 in natural resources called sinks reduces the amount of CO2 that is available to heat the atmosphere and potentially increase climate instability.
List the three main levels of biodiversity and explain why each is important to conserving Earth's biodiversity.
Genetic diversity: the success and survival of a species depend on the variety and relative frequencies of different alleles in the gene pool of a species Species diversity: the variety and relative abundance of the different species that comprise a community are important for the integrity and survival of the community Ecosystem diversity: ecosystem diversity includes the variety of both communities and the nonliving environment on which the communities depend
List four factors that shape the distribution of species.
Geologic history Topography Climate Species interactions
Define global warming and explain how the greenhouse effect has contributed to it.
Greenhouse gases impede the escape of heat from Earth's surface (hold in heat) Long-term increase in the temperature of Earth's lower atmosphere
Compare "gross" and "primary" productivity.
Gross primary productivity is ecosystem's total rate of photosynthesis Net primary productivity is rate at which producers store energy in tissues in excess of their aerobic respiration
List five ways that humans threaten biodiversity.
Habitat destruction Overexploitation Harmful interaction with invasive species Pollution Global warming
Define the following terms; Herbivores, Carnivores, Parasites, Omnivores, Decomposers & Detritivores
Herbivore: an animal that feeds on plants Carnivore: An animal that feeds on flesh parasites: An organism that lives in or on an organism of another species (its host) and benefits by deriving nutrients at the other's expense. omnivore: An animal or person that eats food of both plant and animal origin. decomposers: An organism, especially a soil bacterium, fungus, or invertebrate, that decomposes organic material. detritivores: An animal which feeds on dead organic material, especially plant detritus.
Discuss how humans have altered biogeochemical cycles and be able to diagram any of the cycles that we covered in lecture.
Human activities have greatly increased carbon dioxide levels in the atmosphere and nitrogen levels in the biosphere. Altered biogeochemical cycles combined with climate change increase the vulnerability of biodiversity, food security, human health, and water quality to a changing climate.
List three ways in which humans have increased nitrogen in water and explain why excess nitrogen can be harmful.
Humans increase rate of nitrogen loss by clearing forests and grasslands Humans increase nitrogen in water and air by using fertilizers and by burning fossil fuels Too much or too little nitrogen can compromise plant health
List and describe the three components of any biogeochemical cycle.
Hydrologic cycle Water Atmospheric cycles Nitrogen Sedimentary cycles Phosphorus, carbon, and sulfur
List the estimated dollar value of ecosystem services and what proportion of the Earth's gross economic value that represents.
In 1997, an international team calculated that ecosystem services provide $33 trillion in benefits to humanity yearly—twice the world's gross national product
List the average ecological footprint of a human and how many Earths it would take to satisfy this demand.
In 2005, the biocapacity available for each of Earth's 6.5 billion people was 5.2 acres, but the average human footprint was 6.7 acres Therefore, we exceeded biocapacity by almost 30%, meaning that we would need 1.3 Earths to support humanity at 2005 consumption and population levels
Explain why it is more important to have low nitrogen detergents rather than low phosphorous detergents in Western Oregon.
In Western Oregon, adding nitrogen alters ecosystem function and leads to eutrophication because nitrogen is a very limited resource.
Discuss the importance of seasonal overturn in lakes and list several ways that humans are impacting freshwater lakes.
In spring and fall, temperatures in the lake become more uniform Oxygen-rich surface waters mix with deeper oxygen-poor layers Nutrients that accumulated at bottom are brought to the surface
Describe thermal layering in a lake and describe its impacts in spring, summer, fall, and winter.
In temperate-zone lakes, water can form distinct layers during summer
Describe how a chemoautotroph (engages in chemosynthesis) produces food and discuss why they are important components of the food web associated with hydrothermal vents.
In this community, sulfur bacteria serve as the primary producers, harvesting energy from hydrogen sulfide released from cracks in the Earth's surface in a process called chemosynthesis
Discuss kelp forests listing where they are located and why are they important.
Kelp forests—dense stands of kelp (large brown alga)—are found throughout the world in cool waters of the nearshore zone enriched by nutrient upwelling Kelp provides food and shelter for animals of nearly every phylum, including worms, sea anemones, sea jellies, sea urchins, sea stars, snails, lobsters, crabs, fish, seals, and otters
Define "soil horizon" and compare organic and mineral content in each layer.
Layer structure of soil (each layer is termed soil horizon) Soil characteristics determine what plants will grow and how well
Define the term "desert" and discuss several ways that humans are impacting them.
Less than 10 centimeters annual rainfall, high level of evaporation Tend to occur at 30 degrees north and south and in rain shadows One-third of land surface is arid or semiarid
If the ozone layer was to disappear, what would be the outcome?
Molecules of ozone absorb most layers of ultraviolet light Protects living organisms from excess exposure to UV light
Explain the importance of wild food sources and why they are disappearing.
Many humans rely on wild food sources for the majority of their animal proteins. About one billion people in the world rely on wild caught fish for the majority of their protein. Most large fish species are over harvested leaving smaller less desirable species to be harvested. The collapse of these fisheries leads to societal problems when fishermen no longer have work and sources of protein are diminished. The loss of these large fish species endangers the aquatic ecosystems they are part of and lead to changes in the ecosystem that could cause the system to crash and potentially never recover.
Discuss the nitrogen cycle listing its reservoir and exchange pools.
Nitrogen is used in amino acids and nucleic acids Main reservoir is nitrogen gas in the atmosphere
Explain why there is seasonal variation on the planet Earth and describe where on the Earth is the greatest difference in seasonal patterns.
Northern end of Earth's axis tilts toward sun in June and away in December Difference in tilt causes differences in sunlight intensity and day length
Define the term "nutrients" and explain how they are recycled and reused by all organisms.
Nutrients are atoms and molecules that organisms obtain from living and non-living components of the environment. Nutrients cycle through nutrient cycles and have been used over and over again by organisms since living things have existed (~3.5 billion years)
List and describe the conditions that life needs to survive.
Nutrients from which to construct living tissue Energy to power metabolic activities Liquid water to serve as medium in which metabolic activities occur Appropriate temperatures at which to carry out these processes
List the global reservoirs for water differentiating between salt and fresh water storage areas.
Oceans Polar ice, glaciers Groundwater Lakes, rivers Soil moisture Atmosphere (water vapor) in order: 1,370,000 29,000 4,000 230 67 14
Compare oligotrophic and eutrophic lakes.
Oligotrophic: deep, nutrient-poor, has low primary productivity Eutrophic: shallow, nutrient-rich, has high primary productivity
List the three layers of the atmosphere.
Outer mesosphere Middle stratosphere (includes ozone layer) Inner troposphere (where air is warmed by the greenhouse effect)
Discuss the phosphorous cycle listing its reservoir and exchange pools.
Phosphorus is part of phospholipids and all nucleotides It is the most prevalent limiting factor in ecosystems Main reservoir is Earth's crust; no gaseous phase
Compare the photic and aphotic zones in the ocean and discuss why upwelling is so important in the ocean.
Photic: The photic zone occurs in the upper layer of water, where light is strong enough to support photosynthesis This zone extends down to about 650 feet Aphotic: The aphotic zone lies beneath the photic zone and extends to the ocean floor, which may be as deep as 36,000 feet Light is inadequate for photosynthesis In its upper region, a murky twilight prevails In deeper water, there is constant midnight Nearly all of the energy to support life comes from the dead bodies and excrement sinking down from above Most nutrients are at or near the ocean bottom
Define phytoplankton and zooplankton and discuss their importance to the ecosystem.
Phytoplankton are photosynthetic and act as the primary producers in an aquatic environment. Zooplankton are heterotrophic and consume smaller plankton. Producers
Define nitrogen fixation and list two species that can perform this function.
Plants cannot use nitrogen gas Nitrogen-fixing bacteria convert nitrogen gas into ammonia (NH3) Ammonia and ammonium can be taken up by plants
What is a biodiversity hotspot and why are they important?
Portions of biomes that show the greatest biodiversity Conservationists are working to inventory and protect these regions 24 hot spots hold more than half of all terrestrial species
Discuss differences in primary productivity in tropical, temperate, and polar oceans.
Primary producers are usually the phytoplankton Productivity can vary seasonally North Temperate: March-April peak Tropical: March-April Peak North Polar: July Peak
List three reasons that humans should preserve biodiversity for recreation purposes.
Recreation—many recreational pursuits rely on our unique biodiversity , such as birdwatching, hiking, camping and fishing.
Discuss how environmental laws have curbed the destruction of certain ecosystems.
Recycle (& then recycle properly) Implementing recycling habits into your daily life is one of the most effective ways to help lessen landfill waste, conserve natural resources, save habitats, reduce pollution, cut down on energy consumption, and slow down global warming.
Where in the atmosphere is the ozone layer located?
Region 17 to 27 kilometers above sea level in the stratosphere
Define "Biome"
Regions of land characterized by habitat conditions and community structure
Explain why primary productivity varies.
Seasonal variation Variation by habitat The harsher the environment, the slower plant growth, the lower the primary productivity
Define and discuss as well as provide an example of dry shrublands and woodlands (Chaparral)
Semiarid regions with cooler, wet winters and hot, dry summers Tend to occur in western or southern coastal regions between latitudes of 30 and 40 degrees
Define habitat fragmentation and describe how habitat corridors work to diminish the problems associated with fragmentation
Species habitats do not have to be totally eliminated to be a threat to many species Some species need hundreds of acres to find food and to breed Habitat fragmentation threatens wildlife by splitting up natural ecosystems into small pieces, surrounded by human activities that are incompatible with the survival of many species
Define "Biosphere"
Sum total of the places in which organisms live Includes portions of the hydrosphere, lithosphere, and atmosphere
Explain why DDT was banned in the United States.
Synthetic pesticide banned in United States since the 1970s Birds that are carnivores accumulate DDT in their tissues, produce brittle egg shells
Discuss differences between temperate rainforests and Taiga and list several ways that humans are impacting them.
Temperate rain forests are relatively rare, located on the U.S. Pacific Coast, the southeastern coast of Australia, the southwestern coast of New Zealand, and in parts of Chile and Argentina Abundant precipitation and mild winters mean that moisture is available year round In North America, this biome receives more than 55 inches of rain annually Because of the abundance of water, plants do not need to shed their leaves, and almost all of the trees are coniferous Taiga, also called the northern coniferous forests or Boreal Forests, is located north of the grasslands and temperate forests of North America and Eurasia This is the largest terrestrial biome on Earth, stretching across North America, Scandinavia, and Siberia, nearly encircling the globe Conditions in the taiga are much harsher than in temperate deciduous forests There are long, cold winters and short growing seasons About 16-40 inches of precipitation occurs annually, largely as snow Conifers are the dominant tree in the taiga These trees have narrow, waxy needles to reduce evaporation during winter Clear Cutting
What percentage of ecosystems on Earth are degraded by human activities?
The 2005 Millennium Ecosystem Assessment concluded that 60% of all Earth's ecosystem services are being degraded and used in an unsustainable fashion
Discuss aquifers and how they are being depleted.
The Ogallala aquifer is one of the biggest in the world. Supplies water to 30% of the irrigated agricultural land in the United States. Supplies drinking water to 80% of the people living in the high plains. Has been depleted by approximately 10%. Will take 6000 years to be replenished by natural processes.
Compare and contrast the biological and the phylogenetic definitions of species.
The biological species concept defines species as "groups of interbreeding natural populations that are reproductively isolated from other such groups" The phylogenetic species concept defines a species as the "smallest diagnosable group that contains all the descendants of a single common ancestor"
Define and discuss taxonomy
The branch of biology that is concerned with naming and classifying organisms
How many species are discovered each year?
The current rate of species discovery is approximately 17,000 - 20,000 per year.
Explain why planting diverse crops helps ensure sustainable farming practices.
The diversity of income reduces the overall financial risk to the grower.
Describe photosynthesis and provide its equation.
The energy from the sun is captured by pigment molecules that capture specific wavelengths of light. This energy is then used in reactions that store that energy in chemical bonds. Photosynthetic organisms take in nitrogen, phosphorous, oxygen, and carbon (as well as other molecules) and produce sugars, proteins, lipids, nucleic acids and other biological molecules to sustain life. Photosynthetic organisms serve as a conduit for energy and nutrients because of their ability to uptake nutrients using the energy from the sun converting it into biological molecules. Water + Carbon dioxide + Suns energy Oxygen + Sugar (6H2O + 6CO2 + Sun's Energy 6O2 + C6H12O6)
Compare reservoirs and exchange pools in a biogeochemical cycle.
The flow of a nutrient from the environment to living organisms and back to the environment Main reservoir for the nutrient is in the environment
What is a mass extinction and how many are known from the fossil record?
The fossil record indicates that extinctions occur naturally at a very slow rate, called the background extinction rate However, the fossil record provides evidence that five previous mass extinctions led to the eradication of many species in a relatively short time
Describe the air circulation patterns of the Earth and explain why most desserts are located at 30 degrees latitude.
The greater the distance from the equator, the more pronounced the seasonal changes
Define "ecological footprint".
The human ecological footprint estimates the area of Earth's surface required to produce the resources we use and to absorb the wastes that we generate, expressed in acres of average productivity
What is the main reason that mass extinctions have happened in the past and how does this relate to the current mass extinction?
The most recent major extinction happened roughly 65 million years ago, ending the age of the dinosaurs The causes of mass extinctions are uncertain, but sudden changes in the environment, such as by an enormous meteor impact or by rapid climate change, are likely explanations
Define and discuss the nearshore and intertidal areas of the ocean listing several ways that humans impact the coastal areas.
The nearshore zone is relatively shallow waters where the land that forms the continents gradually slopes downward This zone includes estuaries, which are wetlands that form where rivers meet the oceans The productivity of freshwater and saltwater wetlands is second only to that of rain forests The intertidal zone is a region that is alternately covered and uncovered by the rising and falling tides Intertidal organisms must be adapted to withstand exposure to air as well as pounding waves, and include barnacles, mussels, sea stars, sea urchins, and anemones
List and discuss the current number of named species versus the estimated number of species - why is there such a discrepancy?
The number of named species is currently about 1.5 million (biased toward large organisms in temperate regions) It is estimated that 7 million to 10 million species may exist
List the total number of threatened animals as well as the percentages of birds, mammals, amphibians, and reptiles threatened with extinction.
The results reveal 21 percent of all known mammals, 30 percent of all known amphibians, 12 percent of all known birds, and 28 percent of reptiles, 37 percent of freshwater fishes, 70 percent of plants, 35 percent of invertebrates assessed so far are under threat.
Describe the single most damaging human activity degrading natural habitat and list several reasons why this activity is problematic to biodiversity.
The root causes of environmental degradation are simple: too many people using too many resources and generating too much waste The human population cannot continue to grow No matter how simple our diets, how efficient our housing, how low impact our farming techniques, or how much we reuse and recycle, population growth will eventually overwhelm our best efforts
Discuss human population growth and how the current human population is causing environmental harm.
The root causes of environmental degradation are simple: too many people using too many resources and generating too much waste The human population cannot continue to grow No matter how simple our diets, how efficient our housing, how low impact our farming techniques, or how much we reuse and recycle, population growth will eventually overwhelm our best efforts
Discuss the differences between Savannahs and grasslands and list several ways that humans are impacting them.
The savanna biome is found where tropical scrub forests give way to grasslands Savanna grasslands have a rainy season during which nearly all of the year's precipitation occurs (12 inches) The African savanna has the most diverse and impressive array of large mammals on Earth Most grasslands, or prairies, are located in the centers of continents, such as in central North America and Eurasia Prairies receive 10-30 inches of rain annually They have a continuous cover of grass and virtually no trees except along rivers Grasslands lack trees because the frequent droughts of the prairies can be tolerated by grasses but not trees Historically, trees were burned by fires caused by lightning or by Native Americans, who set fires to maintain grazing lands for bison In tallgrass prairies, as found in Iowa, Missouri, and Illinois, grasses reach up to 6 feet in height Shortgrass prairies receive less rainfall than tallgrass prairies, extending from mid-Texas north into Canada Trees cannot tolerate the hot, dry summers and frequent droughts Nearly all tallgrass prairies have been plowed for agriculture Tallgrass prairie is largely confined to protected areas and is one of the most endangered ecosystems in the world; only 1% remains Shortgrass prairies are often overgrazed by cattle, allowing woody sagebrush to flourish
Define biogeography.
The study of the distribution of organisms and the processes that underlie distribution patterns
Discuss why it is important to list organisms by their scientific name rather than their common name.
The two-part scientific name of an organism is formed from the genus and species A genus is a group that includes a number of very closely related species A species within a genus includes populations of organisms that can potentially interbreed under natural conditions Each two-part scientific name is unique and recognized worldwide Genus and species names are always underlined or italicized The first letter of the genus name is always capitalized The first letter of the species name is always lowercase The species name is always paired with its genus name
How do ecosystems prevent floods and erosion from occurring?
The vegetation in wetlands also helps reduce the speed of water as it flows over the landscape. In combination, wetlands provide immense water storage benefits while slowing water to reduce the height of floods and erosion rates. ... When a natural wetland is drained, the soil and water flow patterns are usually changed.
Define minimum viable populations (MVPs) and list four natural events that make MVPs necessary.
To be functional, a preserve much support a minimum viable population (MVP), the smallest isolated population that can persist in spite of natural events, including inbreeding, disease, fires, and floods The MVP for any species is influenced by many factors, including the quality of the environment, the species' average life span, its fertility, and the number of young that reach maturity
List and discuss several effects of an El Nino climatic event.
Trade winds weaken and warm water flows east across the Pacific Sea surface temperatures rise Upwelling along western coasts ceases Heavy rainfall occurs along coasts, droughts elsewhere
Explain how ocean currents control weather patterns, "why is England warmer than other areas at the same latitude?"
Upper waters move in currents that distribute nutrients and affect regional climates
Define ocean upwelling and discuss why it controls fish populations on the Oregon Coast.
Upward movement of water along a coast; replaces surface waters that move away from shore
Define global warming and list several problems associated with global warming.
Warming waters causes bleaching of coral reefs, leading to their death Coral reefs are home to about 1/3 of all marine fish (about 400 species) despite only being 1% of all marine habitat. Coral reefs are also threatened by over fishing for food species as well as the harvest of pet species for the aquarium pet trade.
Define and discuss wetlands and bogs listing their important functions and list several ways that humans are impacting them.
Wetlands are regions where soil is covered or saturated with water Many aquatic and some terrestrial plant species thrive in wetlands, which support dense growths of algae and phytoplankton, as well as both floating and rooted plants Wetlands act as giant sponges, absorbing water and then gradually releasing it into rivers or aquifers, which action safeguards against flooding and erosion and maintains summer stream flows Wetlands filter and clean water
Define bioluminescence and list advantages it may give organisms that displays it.
While the functions of bioluminescence are not known for all animals, typically bioluminescence is used to warn or evade predators), to lure or detect prey, and for communication between members of the same species.
List three reasons why humans should preserve Earth's genetic resources.
biodiversity provides functioning ecosystems that supply oxygen, clean air and water, pollination of plants, pest control, wastewater treatment and many ecosystem services.
Compare detrital and grazing food webs.
detrital focus on decomposers and detritivores while grazing focuses on herbivores, carnivores, and decomposers
Discuss the value of ecosystem services and functions and list several of those services and functions.
food (including seafood and game), crops, wild foods, and spices. raw materials (including lumber, skins, fuel wood, organic matter, fodder, and fertilizer) genetic resources (including crop improvement genes, and health care) water purity. biogenic minerals.
List four direct ecosystem services.
food plants and animals • building materials • fiber and fabric materials • fuel • medicinal plants • oxygen replenishment
Discuss phylogeny and how it relates to evolutionary history.
in scientific terms, the evolutionary history and relationship of an organism or group of organisms is called its phylogeny. A phylogeny describes the relationships of an organism, such as from which organisms it is thought to have evolved, to which species it is most closely related, and so forth.
What is the ozone layer comprised of?
is composed of the ozone gas (90% of the total ozone in the atmosphere). The ozone has three oxygen atoms, and it is the result of the action of Ultra Violet (UV) radiation on oxygen molecules, composed oftwo oxygen atoms.
Define conservation Biology.
is the branch of biology dedicated to understanding and preserving Earth's biological diversity
Define biodiversity.
is the variety of living organisms that inhabit Earth, their genes, and their habitats.
List four indirect ecosystem services.
maintaining soil fertility • pollination • seed dispersal • waste decomposition • regulation of local climate • flood control • erosion control • pollution control • pest control • wildlife habitat • repository of genes
List one way that carbon dioxide is removed from the atmosphere.
photosynthesis
Explain why there are a finite number of trophic levels possible in a food web.
there are so many species that consume different species
Where is the carbon on earth located?
•Sediments and Rocks 77,000,000 (10^15 grams) •Ocean (Dissolved forms) 39,700 •Soil 1,500 •Atmosphere 750 •Biomass on Land 715
