Bio 2 Exam 4 Review PDF

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Chapter 52: Introduction to ecology and the biosphere 1. List biotic and abiotic factors that limit the distribution and abundance of organisms, in both terrestrial and aquatic ecosystems  Biotic: interactions among living things  Predation  Competition  Disease  Abiotic: interactions between o...

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Chapter 52: Introduction to ecology and the biosphere 1. List biotic and abiotic factors that limit the distribution and abundance of organisms, in both terrestrial and aquatic ecosystems  Biotic: interactions among living things  Predation  Competition  Disease  Abiotic: interactions between organisms and their nonliving environment  Geographic barriers  Temperature  Water  Sunlight  Nutrients  Salinity  pH 2. Recognize that temperature and water levels are the abiotic factors that most influence distribution of the major terrestrial biomes  Temperature  effects on most every biological process  Most organisms cannot regulate body temperature precisely  Effects: Metabolic disturbances, freezing, biomolecule melting, etc.  Majorly affects distrubtuion of a species in an area 3. Describe how temperature, water levels and geographic barriers limit the ranges of organisms at different time scales  Low Temperature o Frost is the most important factor limiting geographic distribution of tropical and subtropical plants o Cold temperatures regulate the distributions of many tropical reptiles o Arizona cactus distribution limited to places where the temperature does not remain below freezing for more than one night o Coral reef organisms abundant only in warm water due to effects of temperature on coral deposition  High Temperature o Corals expel symbiotic algae when temperatures are too high

o Giant sequoias depend on fire to enhance seed release and clear out competing vegetation 4. Explain how global warming influences the distribution of species  Geographic shifts in species’ ranges  Global warming causes species stress, causing species to migrate to higher, cooler locations  Shifts in timing of seasonal traits (phenology)  Changes have been observed in the timing of several seasonal events, e.g. spring blooms, mating season, migration, etc  Extinction  Global warming has already claimed a number of species  Narwhals are currently listed as the marine mammal most threatened by global warming  Ecosystem level effects  Coral bleaching threatens coral ecosystems  Dinoflagellates, single-celled photosynthetic algae, live within the bodies of the coral individuals.  High temperatures seem to cause bleaching events, though the mechanism is unclear 5. Define the following terms: ecology, climate, biome, abiotic, biotic, ectotherm, endotherm, species range, species distribution  Ecology- The study of how organisms interact with each other and their environment.  Climate- The long-term prevailing weather conditions at a given place.  Biome- Any of the world’s major ecosystem types, often classified according to the predominant vegetation for terrestrial biomes and the physical environment for aquatic biomes and characterized by adaptations of organisms to that particular environment.  Abiotic- Nonliving; referring to the physical and chemical properties of an environment.  Biotic- Pertaining to the living factors—the organisms—in an environment.

 Ectotherm- Referring to organisms for which external sources provide most of the heat for temperature regulation.  Endotherm- Referring to organisms that are warmed by heat generated by their own metabolism. This heat usually maintains a relatively stable body temperature higher than that of the external environment.

Chapter 53: Population Ecology 1. Explain how a population's per-generation growth rate can be calculated using the net reproductive rate (R0)  Average number of offspring born per year is lx*mx o The sum of all lx*mx is R0

lx*mx NEEDS TO BE CALCULATED FIRST. THEN ADD ALL OF THEM  If R0 is GREATER than 1, the population is increasing  If R0 is LESS than 1, the population is decresing o Calculate total # of offspring born= sum of all lx*mx o lx is the survival rate ( this would be 1, .9, .5, etc) o mx is the # born per individual (this would be like .1, 2, 0, etc) o TO DISCOVER THE # OF OFFSPRING BORN IN A SPECIFIC AGE GROUP, MULITPLY # ALIVE BY # BORN PER INDIV.  To calculate the size of the next generation( Nt+1) you need the population size and the sum of lx*mx Total of female offspring per female multiplied by total females in the population 2. Explain how the growth of populations over time can be predicted using the per capita growth rate r dN is the population dt is the time

Example:  100 births in a population of 1000 dear  0.10  50 deaths in a popilation of 1000 dear  0.05 r= (.10-.05) =0.05 dN/dt=rN= (.10-0.05)1,000=50 The population should increase by 50 in a year 3. Distinguish between exponential growth and logistic growth, and recognize that resource limitation slows population growth  Exponential growth: population growth is exponential, and the value of r determines the slope

 Logistic growth: pattern where growth slows down as it approaches K  For most species, resources become limiting as populations grow  Carrying capacity (K) or upper boundary for population  If the carry capacity (K) is GREATER than the population number, the population will grow  If the carry capacity (K) is LESS than the population, number, the population will shrink

4. Describe how density-dependent and density-independent processes can limit population size  Density-dependent factors are those whose influence varies with the density of the population. If there were a disease spreading through mice, then that would affect the population number of hawks.  Examples: parasitism, predation, and competition  Density-independent factor are those whose influence is not affected by changes in population size or density. Whatever the number in the population, there could still be a hurricane.  Examples: Generally physical factors, such as weather, drought, flood, fire 5. Compare and contrast the characteristics of species which display r-selected and K-selected life history strategies  r-selected species – high rate of per capita population growth, r, but poor competitive ability (weeds) (examples, mosquitos, ants, flies)  K-selected species – more or less stable populations adapted to exist at or near carrying capacity, K (Examples, humans, rhinos, elephants)

6. Predict future population growth of a specific human population based on age structure and total fertility rate, and describe how the ecological footprint of a human population influences the earth's carrying capacity for humans  Ecological footprint: aggregate total of productive land needed for survival in a sustainable world  Total fertility rate: Number of offspring per female. 2.3 offers zero population growth.

7. Define the following terms: population, carrying capacity, exponential population growth, logistic population growth, per capita growth rate, net reproductive rate, density-dependent, density-independent, r-selected species, Kselected species, ecological footprint

 Population- group of interbreeding individuals occupying the same habitat at the same time  Carrying capacity- The maximum population size that can be supported by the available resources, symbolized as K.  Exponential population growth- Growth of a population in an ideal, unlimited environment, represented by a J-shaped curve when population size is plotted over time.  Logistic population growth- Population growth that levels off as population size approaches carrying capacity.  Per capita growth rate  Net reproductive rate  Density-dependent- Referring to any characteristic that varies with population density.  Density-independent- Referring to any characteristic that is not affected by population density.  r-selected species  K-selected species  Ecological footprint- The aggregate land and water area required by a person, city, or nation to produce all of the resources it consumes and to absorb all of the waste it generates.

Chapter 54: Community Ecology 1. Explain how species diversity varies with latitude and area, and discuss the key factors that explain those gradients, recognizing that none of them on their own explains all patterns of global diversity  Latitudinal gradient: number of species increases from polar to temperate to maximum in tropical areas  Regional richness patterns:  Number of species increases by topographical variation

 Reduced by peninsular effect  Three Hypothesis’s that explain the gradient 1) Time Hypothesis o Communities diversify, or gain species, with time o Temperate regions are younger because they have only more recently recovered from glaciation 2) Area Hypothesis o larger areas have more species because they can support larger populations and a greater range of habitats  Important at regional scales, such as islands 3) Productivity Hypothesis o Greater production of plants results in greater overall species richness 2. Differentiate between primary and secondary succession, and explain the processes of facilitation, inhibition and tolerance in succession patterns  Succession- gradual and continuous change in species composition and community structure over time

 Primary Succession- succession on a newly exposed site that was not previously occupied by soil and vegetation  such as a volcanic eruption, can set climax community back to bare rock

 Secondary Succession- succession on a site that has already supported life but that has undergone a disturbance  Moderate disturbance, such as a fire, can set climax community back to an earlier stage

 Facilitation  Inhibition  Tolerance 3. Apply the equilibrium model of island biogeography to make predictions about an island's diversity based on its size and distance from the mainland 4. Define the following terms: community, interspecific interaction, competition, competitive exclusion, ecological niche, resource partitioning, predation, aposematic coloration, cryptic coloration, mimicry, herbivory, symbiosis,

parasitism, mutualism, commensalism, facilitation, species richness, species diversity, biomass, keystone species  Community- assemblage of many populations that live in the same place at the same time  Interspecific interaction- A relationship between individuals of two or more species in a community.  Competition- A -/- interaction that occurs when individuals of different species compete for a resource that limits the survival and reproduction of each species.  Competitive exclusion- The concept that when populations of two similar species compete for the same limited resources, one population will use the resources more efficiently and have a reproductive advantage that will eventually lead to the elimination of the other population.  Ecological niche- The sum of a species’ use of the biotic and abiotic resources in its environment.  Resource partitioning- The division of environmental resources by coexisting species such that the niche of each species differs by one or more significant factors from the niches of all coexisting species.  Predation- An interaction between species in which one species, the predator, eats the other, the prey.  Aposematic coloration- The bright warning coloration of many animals with effective physical or chemical defenses.  Cryptic coloration- Camouflage that makes a potential prey difficult to spot against its background.  Mimicry  Herbivory- An interaction in which an organism eats part of a plant or alga.  Symbiosis- An ecological relationship between organisms of two different species that live together in direct and intimate contact.

 Parasitism- A+/− ecological interaction in which one organism, the parasite, benefits by feeding upon another organism, the host, which is harmed; some parasites live within the host (feeding on its tissues), while others feed on the host’s external surface.  Mutualism- A+/+ ecological interaction that benefits each of the interacting species.  Commensalism- A+/0 ecological interaction in which one organism benefits but the other is neither helped nor harmed.  Facilitation  Species richness- the number of species in a community. The variety of different tree species.  Species evenness- how close are the relative abundances of the different species. If there is 5 oak trees and 1 Palm tree then the area isn’t very even.  Biomass- The total mass of organic matter comprising a group of organisms in a particular habitat.  Keystone species- A species that is not necessarily abundant in a community yet exerts strong control on community structure by the nature of its ecological role or niche.

Chapter 55: Ecosystem and restoration ecology 1. Understand that in ecosystems, materials are recycled while energy is eventually lost, and describe why energy is lost as it moves through trophic levels  Energy is lost as it moves through a food web in two ways  Production efficiency where energy is lost in a single trophic level  Percentage of energy assimilated by an organism that becomes incorporated into new biomass  Energy is lost to heat and in feces  Trophic-level transfer efficiency where energy is lost as it is transferred from one trophic level to the next  amount of energy at one trophic level that is acquired by the trophic level above and incorporated into biomass

 Averages around 10% with much variation (e.g. >30% some marine food webs) 2. Draw a typical pyramid of energy, biomass and numbers based on a typical food web

 The number of individuals per trophic level usually decreases as you move to higher trophic levels

 The amount of biomass per trophic level usually decreases as you move to higher trophic levels

 The rate of energy flow per trophic level must decrease as you move to higher trophic levels 3. Describe the factors that limit primary production in terrestrial and aquatic ecosystems TERRESTRIAL  Water: In terrestrial systems, positive relationship with annual precipitation  Temperatures: Evapotranspiration rate can predict aboveground primary production  Evapotranspiration rate can predict aboveground primary production  The amount of water evaporating from plants is dependent on both water and temperature  Nutrients (nitrogen and phosphorus): Can be limiting factor  Liebig’s law of the minimum – species biomass or abundance is limited by the scarcest factor  Primary producers need carbon, but they also need nitrogen, phosphorus, and other elements. AQUATIC  Limited mainly by light and nutrient availability  Deep ocean (lack of light) and open ocean (lack of nutrients) display low primary productivity 4. Describe the nitrogen, phosphorus, carbon and water cycles, and predict the effects of perturbations to these cycles

 Carbon cycle is affected by burning fossil fuels  Burning fossil fuels is adding CO2 and particulate matter to the atmosphere  and is affected by deforestation, as forests store carbon

 Fertilizer runoff of fertilizer can lead to eutrophication of water bodies and subsequent depletion of water oxygen levels

 Nitrogen cycle is also affected by fertilization, as human alterations of the nitrogen cycle have approximately doubled the rate of nitrogen input to the cycle

 Water cycle is affected by deforestation  Because plants play a key role in the water cycle via evapotranspiration, desertification can occur in an ecosystem where plants have been removed 5. Define the following terms: ecosystem, trophic level, food chain, food web, producer, consumer, production efficiency, gross primary production, net primary

production, secondary production, eutrophication, detritivore, decomposer, detritus, nutrient  Ecosystem- biotic community of organisms in an area plus the abiotic environment affecting that community  Trophic level  Food chain- linear depiction of energy flow, where each feeding level in a chain is a trophic level  Food web- more complex and more realistic models have interconnected food chains  Producer- An organism that produces organic compounds from CO 2 by harnessing light energy (in photosynthesis) or by oxidizing inorganic chemicals (in chemosynthetic reactions carried out by some prokaryotes).  Consumer- eat other organisms in an ecosystem  Production efficiency- The percentage of energy stored in assimilated food that is not used for respiration or eliminated as waste.  Gross primary production- The total primary production of an ecosystem.  Net primary production- The gross primary production of an ecosystem minus the energy used by the producers for respiration.  Secondary production- The amount of chemical energy in consumers’ food that is converted to their own new biomass during a given time period.  Eutrophication- A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria.  Detritivore/ Decomposer- eat detritus – unconsumed plants, remains of animals, and waste products  Detritus- unconsumed plants, remains of animals, and waste products

 Nutrient

Chapter 56: Conservation Biology and climate change 1. Explain the four main threats to the world's biodiversity: habitat destruction, introduced species, exploitation and climate change 2. Define inbreeding and explain how it can be detrimental to populations 3. Explain why small populations are at greater risk of extinction 4. Describe the basic principles of reserve design and explain both sides of the SLOSS debate 5. Describe the human activities that are responsible for nutrient enrichment in aquatic ecosystems, and the consequences for those ecosystems 6. Define the following terms: biodiversity (including genetic diversity, species diversity, ecosystem diversity), ecosystem service, habitat fragmentation, minimum viable population, effective population size, biomagnification, sustainable development  Biodiversity  Genetic diversity  Species diversity- The number and relative abundance of species in a biological community.  Ecosystem diversity  Ecosystem service  Habitat fragmentation  Minimum viable population- The smallest population size at which a species is able to sustain its numbers and survive.  Effective population size- An estimate of the size of a population based on the numbers of females and males that successfully breed; generally smaller than the total population.

 Biomagnification  Sustainable Development- Development that meets the needs of people today without limiting the ability of future generations to meet their needs....