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220 Cards in this Set
- Front
- Back
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what does the word ecology actually mean?
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from the greek oikos and logia= the study of the house.
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What is ecology the study of?
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how organisms interact with their environment.
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What is the main goal of ecology?>
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to understand the distribution and abundance of organisms.
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What are the major points of ecology?
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species are limited in their distribution.
abundance varies from place to place. ( something environmental limits their living) |
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What is environmentalism?
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social movement that believes that human actions are leading to degradation of planet
they object on aesthetic moral and pragmatic grounds They often use ecological information for guidence on important environmental issues. example: Rachel Carson= "SiWhalent Spring" |
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What are some questions ecologists address?
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Why are cardinals common around saint louis but rare in Minnesota?
Why are Great crested Flycatchers not found in the western part of the U.S? |
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What are the different levels of ecological inquiry?
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1. organismal ecology/ behavioral ecology
2. populationj ecology 3. community ecology 4. Ecosystem ecology |
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organismal/behavioral ecology facts?
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Questions= What physiological/behavioral adaptations affect the fitness of individuals?
Parental Care Example. explain. |
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Population ecology?
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Queston=What factors affect the abundance of a species?
Climate, Dams, Human induced mortality. |
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Community ecology?
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Questions= How do species interact?
How do those interactions affect distribution and abundance? Food webs! |
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Ecosystem ecology?
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Questions: how do chemical elements and energy flow through species in an ecosystem?
What effect does that have on species? example: salmon as ecosystem engineers. explain |
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Applied Ecology/ Conservation Biology
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Questions: Why are the populations of many species declining?
What can be done to minimize the extinctin of species? Both abiotic and biotic factors affect species persistance. Fundamental and Realized niche. |
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Fundamental niche?
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abiotic range of conditions favorable to species.
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Realized niche?
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fundamental niche modified by biotic interactions (competition and predation)
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What are the two main abiotid factors that affect a species distribution and abundance?
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temperature and precipitation!
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What do species differ in their adaptations (tollerance)
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heat/cold and wet/dry conditions
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What does the variation in climate on the earth create?
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different combinations of temperature and precipitation that produce different types of biomes!
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What is a biome?
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an ecosystem characterized by unique types of vegetation.
as we move further away from the poles, the temperature decreases. |
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What are all of the terrestrial biomes?
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tropical rain forest
subtropical desert temperate grassland temperate forest boreal forest arctic tundra |
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tropical rain forest?
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found in equatorial regions where temperatures and rainfall are high, variation int emperature is low, and enough rainfall is available to support year round growth.
example. Belem, Brazil which is near the equator. high productivity and aboveground biomass. a lot of species diversity! canopy trees and epyphytes (plnats that grow entirely on other plants) |
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productivity?
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the total amount of carbon fixed by photosynthesis per unit area per year.
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aboveground biomass?
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total mass of living plants, excluding roots.
reflects net primary productivity. |
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net primary productivity?
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the total amount of carbon that is fixed per year minus the amount of fixed carbon oxidized during cellular respiration.
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subtrapical deserts?
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are found long or near the equator also.
low precipitation! Because conditions are rarely good enough to support photosynthesis, the productivity of desert communities is a tiny fraction of average values for tropical forest communities. Desert species adapt to the extreme temperatures and aridity in 2 ways. 1. they grow at a low rate year-round 2. grow rapidly in response to any rainfall. low species diversity and productivity. |
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temperate grasslands?
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quite dry.
temperate-regions with temperatures that are moderate relative to the tropics and polar regions, and where summers are typically long and warm and winters are short and cold. Grasses are the dominant life-form. found throughout central north america and the heartland of Eurasia. highly seasonal temperatures. which dictates a well definted growing season. also called prairies or steppes. exist because conditions are too dry to support tree growth but too cold, wet and seasonal for drought adapted desert species. soils are often highly fertile! |
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Temperate forest?
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high percipitation!
foudn in easter north america, most of europe, chile and new zealand experience a period in which mean monthly temperatures fall below zfreezing and plant growth stops.dominated by deciduous species whcih drop their leaves in the autumn and grow new leaves in the spring. evergreens are common as well. has tropical leveles that are lower than those of tropical forests yet higher than those of deserts or grasslands. |
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Boreal forest?
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taiga
stretches across most of canada, alska, russia and northern europe. very cold winters, cool, short summersand very high annual variation in temperature. so cold that evaporation is minimal and moisture is usually abundant enough to support tree growth as a result. dominated by highly cold-tolerant conifers: spruce, pine, fir, and larch trees. evergreen species... productivity is low. low species diversity |
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What two hypothesis have been offered to explain why evergreens predominate in cold environments, even though they do not photosynthesize in the winter?
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1. they can begin phtosynthesizing early in the spring, even before the snow melts, when sunshine is intense enough to warm their needles.
2. soils tend to be acidic and contain little available nitrogen. because leaves are nitrogen rich, species that must produce an entirely new set of leaves each year might be at a disadvantage. neither hypothesis has been tested rigorously. |
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arctic tundra?
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the growing season is about 6-8 weeks long, otherwise temperatures are below freezing.
precipitation is also low. treeless low species diversity, low productivity and low aboveground biomass. |
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Aquatic biomes?
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-depth of water and rate of water movement determines the zone.
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Wat are the zones of lakes?
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littoral zone-lots of sunlight, more vegitation, microscopic. right along the edge
limnetic zone-shallow enough for vegitation. phtoic zone- light zone aphotic zone-no light no productivity, nutrients come from other zones. benthic zone-provides habitat for burrowing animals and bacteria. |
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wetlands?
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shallow water habitats where the soil is saturated with water for at least part of the year, distinct from lakes and ponds because they have shallow water and emergent vegitation.
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emergent vegitation?
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meaning plants that grow above the surface of the water.
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marshes?
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lack trees and typically exhibit a slow but steady rate of water flow,, typically connected to a lake or stream systems
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swamps?
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similar to marshes but are dominated by trees and shrubs. very productive like marshes!
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bogs?
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develop in depressions where water flow is low or nonexistent.
unproductive! oxygen poor. |
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marine zones?
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intertidal-near shore, highest productivity
neritic-from the intertidal zone to depths of about 200m oceanic zone-open ocean, the most unproductive environment on earth, nutrients are extremely scarce benthic-more usual for light to be completely absent, depend on rain of organic debris from above, whcih settles into the benthos and forms sediments. |
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Biogeography?
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the study of how the interplay between biotic interactions and abiotic conditions translates into broad scale patterns of biodiversity.
incorparates both contemporary (now, temperature and percipitation) and historical(evolutionary history) factors. |
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History of the study of biogeography?
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1.Aristotle
2.Carolus Linnaeus-believed that god spoke to humans through the natural world and felt it was his duty to catalogue the collections in this divine museum. believed that earth and species were immutable. hypothesized a single origin of diversity on mount Ararat. 3. Comte de Buffon- noted that different areas of the world, although possessing similar climates, had distinctly different species assemblages. diversity orginated on a northern landmass and species became modified after a dispersal into separate environments (jesuit college) 4. Johann Reinhold Forster- circumnavigated the globe with captain cook collecting plants and dfined the biotic regions of teh world based on plant diversity. noted that insular communites had fewer plant species than those of the mainland and that the number of species on islands increased with available resources. 5. karl willdenow- described floristic provinces of europe. suggested that there were several mountain top sites of species origin... mountains in ancient times were seperated by global seas. these distinct mountans served as the source for the floristic regions of the world. |
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What is the source energy for most biological systems?
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the sun!
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What is entropy?
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a measure of order, based on the second law of thermodynamics.
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energy flow?
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1. the sun is the source energy for most biological systems.
2. green plants capture solar energy and convert it to biological energy. 3. net primary productivity= the energy that is invested in new tissue. |
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What are the four components of an ecosystem and energy flows?
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external energy source (sun) >>>>primary producers>>>consumers or decomposers
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how does npp vary amoung ecosystems?
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terrestrial ecosystems- highest in wet tropics (16 percent of landmass, 43% of terrestrial net primary productivity.
-lowest in deserts and arctic regions. |
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what limites productivity?
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in terrestrial systems: temperature and water availability!
--in aquatic systems-nutrients (nitrogen,phosphurus, minerals) |
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How are components organized?
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into trophic levels and food webs!
display precisely how energy flows through ecosystems (how energy moves from one species to another) |
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is energy lost or gained in transfer between trophic levels?
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lost! only 10-20 percent of energy gets transferred between levels.
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What is the relative abundance of species in ecosystems?
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primary producers are most common.
primary consumers(herbivores) are less comomon secondary consumers (carnivores) are rare! |
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How do nutrients move through ecosystems?
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-biogeochemical cycles
-nutrients like energy also moves through ecosystems. (carbon and nitrogen) |
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Glabal nitrogen cycle?
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-nitrogen-4th most common element.
-limiting factor for plant growth *78% atmosphere is nitrogen (N2 form) *plants cannot use this form *plants use nitrogen in form of: nitrate, ammonia -nitrogen fixation results from: lightning, nitrogen fixing bacteria. |
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Have humans altered the nitrogen cycle?
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yes!
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What do community ecologists study?
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1. how species interactions affect distribution and abundance
2. diversity patterns |
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types of species interactions?
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parasitism, predation, herbivory, competition, mutualism, commensalism
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parasitism?
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positive/negative
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predation
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positive/negative
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herbivory
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positive/ negative
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competition
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negative/negative
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mutualism
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positive/positive
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commensalism
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positive/ no effect
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what is competition?
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use or defense of resource by one individual that reduces the availability of the resource to other individuals.
intraspcific(within a species) or interspecific (between species) |
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types of competition?
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1. resource or scramble competitioin (battling for food)
2. contest or interference competition (exhibit behavior to stop others to get what they want) |
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What resources does competition involve?
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food, territories, mates.
1. resources have to be limited. 2. individuals must have shared resources requirements. |
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What are the effects of competition on plant abundance?
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each spring thousands of seeds of annual plants germinate.
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observation?
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population density decreases as season progresses.
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intraspecific competition?
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as plants grow:
-individual plants take up increasing amounts of nutrients, water and spaces (=resources) -some plants are more successful in this than others -prediction- should see loss of individuals in population. -plants will decreases in population density as the total biomass of the population increases. |
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interspecific competition?
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competition requires species use similar resources.
resource requirements a species= niche |
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niche?
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resources necessary for existence.
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strongest competition interactions?
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most similar species!
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why are niches important for ecology?
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allow us to understand interactions between species and thus distribution and abundance.
competition=niche overlap |
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fundamental niche?
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resource use in absence of other species (competitors)
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realized niche?
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competitors! always smaller.
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if niches do not overlap completely what will happen to the weaker competitors?
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weaker competitors use nonoverlapping resources.
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Can two species share the same niche?
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no!
competition exclusion principle! |
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competition exclusion principle?
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2 species with identical niches cannot coexist.
when 2 species compete for a resource: a.better competitor will have higher fitness and will eventually exclude other species b. second species (weak competitor) goes extinct. |
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What did Gause study?
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studied competition in paramecium.
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What can competition do to distribution and abundance?
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it can reduce distrubition and abundance.
it can affect distribution and abundance. |
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Can niches help us to understand competition?
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yes! but niches can change over time.
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Niches can evolve.
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natural selection favors traits that decrease competition (leads to higher fitness)
so we expect evolution to favor individuals (species) that have little niche overlap. |
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predation?
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predator feeds on a prey species.
-affect population abundance of species. |
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mutualism?
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rarer than competition and consumption but can strongly affect the abundance of some species.
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Ecological community?
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association of interacting species in a defined area.
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richness?
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number of species.
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diversity?
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combination of richness and relative abundances of species.
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How do we measure species diversity?
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shannon weaver index to measure probablity!
the higher the score the higher the probability. |
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Shannon Weaver index?
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index increase with richness
index increases with evenness (relative abundance of species) |
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What affects species diversity?
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1. area (species are relationship)
2. habitat diversity 3. predation 4. succession and disturbance |
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What is the only true law in ecology?
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increasing area!
species area relationship |
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Habitats affect diversity?
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as the islands get bigger=more same old.
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predation affects diversity?
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predators-consume prey; reduce prey abundance
increases diversity |
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Keystone predators and diversity?
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-feeds on dominant competitor
-keeps abundance of dominant competitor low -eliminates competitive exclusion by dominant competitor. maintains high levels of diversity. |
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The influence of native and non-native predators on native diversity?
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as the number of native predator species increases, the diversity of native prey species also increases.
however, as the number of non-nativepredator species increases, the diversity of native prey species decreases. |
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Disturbances affect diversity?
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disturbance- event that removes individuals from a community.
natural or human caused |
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What happens after a disturbance?
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succession- development of communities after disturbance.
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2 kinds of succession?
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primary(rare)- all organisms and soil removed. start with sterile ground, slow succession.
secondary(common)-some organisms and soil are in tact! much more rapid. |
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HOw does diversity change after a disturbance?
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1. diversity increases over time following a disturbance.
2. diversity increases and then declines after a disturbance. |
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explain the second option! (IDH)
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diversity is highest at some intermediate time following a disturbance.
grasslands, marine intertidal habitats= intermediate disturbance hypothesis! |
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IDH patterns?
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1. diversity maximum at intermediate time following a disturbance
and/or 2. diversity maximum at intermediate level of disturbance |
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How does IDH WORK?
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High disturbance
-few species adapted to high disturbance low disturbance -community limited to only the best competitors intermediate disturbance -many species adapted to moderate disturbance and moderate disturbance prevents competitive exclusion |
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summary: what are the important factors that affect species diversity in communities?
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area, predation, habitat diversity and disturbance
1. disturbance decreases diversity (deserts and forests) 2. disturbance increases diversity (marine intertidal grasslands) |
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Global diversity patterns!
Pattern 1 diversity hotspots |
-tropical rainforests, tropical coral reefs, large tropical lakes
-temperate shrublands with mediterranean climate CA,S.Africa, SW Australia, Chile, Mediterranean basin -All total, hotspots contain: 25% of all plant species on earth 25% of all animal species on earth |
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Pattern 2 Latitudinal Diversity Gradient?
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-most taxa have highest diversity near equator
-diversity declines as latitude increase (as one moves away from equator) |
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Why does latitudinal diversity gradient exist?
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3 favored hypotheses:
Global energy gradient-solar radiation;NPP highest at equator long term climate stability-less impact on glaciation species area relationship- most area is tropics |
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Why does diversity matter?
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communities with high diversity are
1. more productive 2. more stable/resilient handle stressors better |
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Today?
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Diversity is declining in many communites around the world.
Consequences? communities will become less productive and less stable |
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population?
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a group of individuals from the same species that live in the same place at the same time.
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evolutionary questions?
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how do the genetic characteristics of population change over time?
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ecological questions?
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what factors affect population size?
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properties of populations?
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1. distribution (size, shape, location)
2. dispersion (nearly uniform, random, clumped) 3. size ( how many total) |
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demography?
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study of factors that determine the size and structure of a population over time.
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factors that decrease population size?
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deaths
emigration |
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factors that increase population size?
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births
immigration |
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life tables?
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summarizes important demographic information
allows you to predict future population sizes |
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fecundity?
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average reproductive output.
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survivorship curves?
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data from lifetable allow you to create these curves.
these curves show changes in survivorship with age 3 types of curves exist |
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3 general types of survivorship curves?
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high
low steady |
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Life history pattern continuum?
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differences in survivorship with age reflect different life history patterns.
why? there is a trade off between survival and reproduction. |
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What are life tables and survivorship curves used for?
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to predict population change.
but they are species specific we can devise a more general way to predict population change by population models! |
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population models?
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to understand and predict population dynamics.
not species specific can examine many species simultaneously |
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population growth models
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popuations grow at different rates based on their growth rate.
population growth rate=r r=birth rate-death rate r max= maximum growth rate for a species ( when resources are unlimited) assumes no immigration and no emigration |
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exponential growth model?
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when resources are abundant populations can grow at an exponential rate
DELTA N/DELTA T=r max N change in population size= rmax*population size,N increases in population size do not affect rate of population growth >>Density independent growth population growth not dependent on population size |
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are resources constantly aboundant?
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NO!
density dependent factors reduce resource availability and thus population growth |
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logistic growth model?
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as population size increases, resources are depleted and so population growth rate slows.
population size stops growing at size K, the carrying capacity increases in population size DO affect rate of population growth. |
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k?
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number individuals that the environment can support=population size where birth=death
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Exponential growth vs. logistic?
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exponential= density independent, and no carrying capacity
logistic=density dependent and carrying capacity |
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Resource management?
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people harvest individuals from many populations (deer, elk, pheasant, fish, etc.)
human hunting increases the population death rate pop growth= b-d-human hunting resource managers must predict population growth rate to prevent overharvest many populations are well managed (deer) but many marine fish populations have been and are being overharvested. why? ability to pararize the model |
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endangered species?
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population ecologists create models to predict future population size of endangered species
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disease outbreaks?
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population ecologists predict these...
example. lyme disease, west nile virus ( dry year = more west nile) |
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conservation biology?
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field of science that studies species threatened with extinction.
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recent extinctions?
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terrestrial vertebrates= 1-10
plants=10-100 aquatic inverts=100-1000 terrestrial inverts= 1000-10,000 |
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now vs. before?
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extinction rates are 1000 times higher than in the past!
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why is bio diversity important?
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ecosystem stability
ecosystem services provides goods and services |
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types of diversity?
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genetic diversity
special diversity ecosystem diversity |
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genetic diversity?
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total genetic information contained within, for example a species.
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species diversity?
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richness and abundance
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ecosystem diversity? don't worry about !
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variety of biotic communities in region.??
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3 major factors that cause populations to decline and species to go extinct?
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1. habitat loss/destruction
2. overexploitation/ overharvesting 3. exotic species |
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habitat loss?
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speces are adapted to specific habitat types, (requirements)
population size is affected by the amount of habitat available as habitat area declines, population sizes decline. if habitat area continues to decline populations and species become extinct, population size becomes zero. so habitat loss leads to species extinctions |
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species area curve?
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we know how many species will go extinct as habitat area declines.
empirical relationship between area and number of species! so for all habitat types, as area increasesso do the number of species because resources increase. That means as habitat area declines, resources decline and species go extinct. human activites often lead to habitat area loss |
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overexploitation?
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humans harvest many species for food, sport, and money.
hunting by humans is an extra source of mortality (in addition to disease, old age, and natural predators) |
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Over hunting?
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can cause a rapid reduction in population size and extinction.
was the principle factor causing the extinction of dodo bird |
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exotic species?
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a species that evolved in 1 part of the world and moved by human activity to another part of the world.
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intentional introductions?
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many fish are introduced into lakes for sport
many plants are introduced to improve pasture land or as ornamentals |
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uninted introductions?
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rats, mice, snakes, insects are carried on planes and ships to new locations
aquatic species and insects are transported in ballast in oceanic ships to new locations. |
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exotic species are they a problem?
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no! becuase they fail to establish populations in their new environments because they are not adapted to it.
some are a problem becuae they cause native species to decline or crop loss by 1. carry novel disease 2. competition 3. predation |
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exotic species and disease?
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example. American chestnut tree- 100 years ago, its population size was 3.5 billion
today- few individuals alive. why? in 1904, ny zoological gardem imported exotic asian chestnut trees infected with fungus, endothia parasitica. fungus spread to american chestnut trees and killed them. |
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exotic species and competition?
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zebra mussels- exotic from asia, introduced into great lakes in 1988
-reproduce very fast -grow on native mussles and clams, kill them dozens of native species have declined sharply following the appearance of zebra mussles. |
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Chapter 17!!!!
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:) let's get this done!
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What is the equilibrium constant for a given reaction?
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has constant numerical value for given temperature
value is independent of how equilibrium was reached could start with only no2 use coefficients to find the subscripts |
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If k>>>>1?
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very little product formed, essentialy no reaction!
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If k~1?
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significant amount of reactants and products at equilibrium!
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If Qc(reaction quotient) = Kc(equilibrium constant?
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reaction is at equilibrium!
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If Qc(reaction quotient) not= Kc(equilibrium constant?
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value of Qc tells which way the reaction must proceed to reach equilibrium!
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If Qc<Kc?
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To reach equilibrium the numerator needs to increase, and the denominator needs to decrease!
=forward direction ( shift to right) |
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If Qc>Kc?
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to reach equilibrium, the numerator needs to decrease, and the denominator needs to increase.
so net change in reverse direction (shift to left) |
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Qc and Kc?
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are dimensionles!! no units!
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Qc?
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[C]^c[D]^d/[A]^a[B]^b
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Kc?
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kfwd/krev
kc overall= kc1xkc2 |
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Pure solids or pure liquids?
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DO NOT INCLUDE IN QC OR KC!
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equilibruim for gases?
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use PaV=NaRT = Na/V=Pa/RT
plug in kc into equation! this makes kc = kp times RT! |
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kp?
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kc(RT)^-1
also a constant at constant temperature and partial pressures must be in atmospheres! to convert kc to kp use, R=.0821 Latm/molK |
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Generally for aA(g)+bB(g)....><cC(g)+dD(g) Kp=?
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Kc(RT)DeltaN
Delta N = (c+d+...)-(a+b+..) |
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La Chatelier's principle?
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When system at equilibrium is subjected to a disturbance (stress), the system reacts in a way that partially offsets the stress.
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distrubance (stress)?
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change in temperature, pressure, or concentration of a reactant or product.
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Change in concentration?
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if added to numerator of course QC>KC which means left (reverse favored)
if subtracted from numerator QC<KC which means right (forward favored) if added to denominator= shift in right! if subtracted from denominator= left is favored! |
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If we add pure solid or pure liquid?
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nothing happens as long as some remains!
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Change in pressure? add weight to movable lid?
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add weight to movable lid = volume decreases, pressure increases!
to counteract the increase in pressure, shift to the right, decreases the total moles of gas, reduces the pressure! |
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remove weight from lid?
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volume increases, pressure decreases.
reaction shifts to the left, forms more moles of gas, pressure increases. |
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Change in temperature?
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exothermic=negative
endothermic= postive |
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exothermic?
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reactants<>products + heat
Raise the temperature= shift to the left! lower the temperature= right. |
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endothermic?
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reactants + heat<> products
raise the temperature= shift to right. lower the temperature= shift to left. |
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Catalyst?
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accelarates reaction, changes activation energy
doesn't change kc or identity of reactants and products, same reaction still! has no effect on position of equilibrium = no shifT! |
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ICE CHART?
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initial
change equilibrium remember for reactants to negative! and for products positive! |
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if given concentations and one concentration at equilibrium and need kc and ther concentrations at equilibrium?
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find how much has reacted of the one concentration we have at equilibrium.
use stoichiometry to see how much has formed/ reacted of other concentrations. use ice chart!! |
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if given mol and liters of 2 reactants and kc?
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find MOLARITY!
assume that the products are 0 use ice chart and for x plug in molarity of reactants that react set this kc = to actual kc and solve for x, take the square root of both sides if x2 is there! |
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Qc? if given kc and concentration for all of the reactants and products?
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set the given concentrations to find qc and then figure out if qc is less then or greater than kc.
if kc is bigger than qc the reaction shifts to the right! |
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If given initial concentrations and kc?
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set the ice chart and set kc= to given kc. will give quadratic formula equation!
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What does the reaction between hcl and naoh give?
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WATER!
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Total ionic equation?
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take everything apart! every element!
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net ionic equation?
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cancel out all the same ones.
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When acid dissolves in h2o, what is a part of the reaction?
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the solvent!
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H3O + is the same as?
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H+!
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Arrhenius Acid base theory...
Acid? |
has H in it's formula dn dissociates in H2O to give H30 +
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Base?
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has OH- in it's formula and dissociates in h20 to give oh-
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Acid examples?
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hcl, hno3, hcn
the h atoms are not ions, they are covalently bonded! |
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bases examples?
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naoh, koh, ba(oh)2
these contain oh-, they are ionic compounds! |
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neutralization?
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reaction of acid and base
h+ from acid and oh- from base. |
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arrhenius theory is useful but limited. what are some exmples of bases that don't contain oh-
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nh3 and k2co3
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strong acids?
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dissociate completely into ions in h20!
kc >>>>1 for strong acid! |
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weak acids?
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dissociate only slighlty into ions!
the water concentration is usually much much larger than [HA] changes negligibely during reaction it's a constant! |
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ka?
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kc[H2O]
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stronger acid?
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higher h30=larger ka
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ewaker acid?
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lower h30=smaller ka
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strong acids!? know this!
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1. hcl, hbr, hi!
2. oxoacids where number of O atoms exceeds the number of ionizable h atoms by 2 or more. so more o than h by at least 2!!!!! |
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weak acids?
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hf!
acids wehre h is not bonded to o or halogen! oxoacids where number of o atoms equals or exceeds by 1 the number of ionizable h atoms! so more o by 1 or equal to h. |
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carboxylic acids?
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acetic acid
benzoic acid |
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strong bases?
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1. m20 or moh where m=li,na,k,rb,cs
2. mo or m(oh)2 where m=ca,sr,ba |
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weak bases?
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ammonia : nh3
amines: rnh2, r2nh, r3n |
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autoionization of h20 and ph scale? what is water?
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extremely weak electrolyte
autoionizes(reacts with itself) to very sligh extent! |
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kw?
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[h30][oh-]=
1.0x10^-14 at 25 degrees celsius! |
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in pure h20?
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h30+ and oh- = the same!
= square root of kw very very small concentration of h30 and oh only 1 in 555000000 h20 molecules dissociates to form h30 and oh |
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A change in h30 causes?
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an inverse change in oh and vice versa.
raise h30 and oh is lowered lower h30 and oh is raised |
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both h30 and oh are/
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present in all aqueous solutions!
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in acidic solution?
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h3o>oh
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in neutral solution
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h30=oh = 1x10^-7
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in basic solution?
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h30<oh
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[H30][OH]=KW!
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YAY!
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iN aqueous solution?
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can have a wide range of h30 concentrations
from 10.0 M to 10^-15 M |
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Can discuss using the ph scale!
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neutral solution ph=7
acidic solution ph<7 basic solution ph>7 |
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ph scale =?
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p(oh)=-log[OH-]
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a lower pka corresponds to?
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a larger ka= stronger acid!
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pkw?
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ph+pOH= 14!
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acidic solution?
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larger h30, smaller oh
h30>10^-7, ph<7.0 |
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basic solution?
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larger oh, smaller h30
h30<10^-7, ph>7.0 |
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acid? bronsted lowry
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proton donor.
any species that donates h+ ions must contain h in its formula all arrhenius acids are bronsted lowry acids! |
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base? bronsted lowry?
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proton acceptor
any species that accepts h+ must contain lone pair of electrons to accept h+ |
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h20 is?
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amphoteric, can be an acid or a base, depending on reaction!
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conjugate bases?
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every b-l acid has a conjugate base
every b-l base has a conjugate acid acid is written first! |
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Direction of acid-base reaction?
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can predict if given relative acid/ base strengths
an acid base reaction proceeds to the greater extent in the direction in which a stronger acid and stronger base form a weaker acid and weaker base the stronger the acid teh weaker the conjugate base |
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how to use the table?
if the acid is to the upper left of the base? |
the equilibrium is to the right, forward direction, products formed.
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if the acid is to the lower left of the base?
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equilibrium is to the left, reverse direction, reactants are favored!
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