Bio 181 Unit 2 Flashcards
(71 cards)
1
Q
Ecology
A
Study of relationships between organisms and environment.
2
Q
Organismal Ecology
A
Study of an organism’s relationship with its environment (biotic and abiotic).
3
Q
Population Ecology
A
Study of interactions between members of same species.
4
Q
Abiotic
A
Non-living physical and chemical elements.
- water, air, soil, sunlight, minerals
5
Q
Biotic
A
Living organisms.
- animals, plants, fungi
6
Q
Populations
A
Group of individuals of same species in one place.
7
Q
Three characteristic of populations
A
- Range/area
- Pattern of spacing of individuals
- Change in size through time
8
Q
Density-dependent Factors
A
- predation, inter- and intraspecific competition, accumulation of waste, diseases
- usually, the denser a population is, the greater its mortality rate
9
Q
Density-independent Factors
A
- weather, natural disasters, pollution, and other chemical/physical conditions
- influence population no matter what its density
10
Q
Population Demography
A
- quantitative study of populations
- how size changes through time
- population broken down into parts
- birth and death rates of a specific age
- survivorship: percent of original population surviving to a given age
- survivorship curve: graph of number of individuals surviving at each age interval
11
Q
Demography and Dynamics
A
Population growth most influenced by number of females.
12
Q
Generation Times
A
Average interval between birth of an individual and birth of its offspring.
- Short generation times = increase in size more quickly
- Larger organisms have longer generation times (there are exceptions)
13
Q
Cohort
A
Group of individuals of same age.
14
Q
Fecundity
A
Number of offspring produced in a standard time.
15
Q
Mortality
A
Death rate in a standard time.
16
Q
Life Table
A
Probability of survival and reproduction through a cohort’s life.
17
Q
Age Structure
A
- Number of individuals in different age groups
- Critical influence on population’s growth rate
- Cohort, fecundity, mortality
18
Q
Population Growth
A
Populations often remain same size regardless of number of offspring born.
19
Q
Exponential Growth
A
- Biotic potential of any population is exponential, even when rate of increase remains constant; unchecked = population explosion
- populations eventually reach some limit imposed by a shortage
- birth rate unchanged
- death rate fallen dramtically
20
Q
Exponential Growth Model
A
r = (b-d) + (i-e)
- r: rate of population increase
- b: birth rate
- d: death rate
- i: immigration
- e: emigration
21
Q
Carrying Capacity (K)
A
Maximum number of individuals that environment can support.
22
Q
Logistic Growth
A
Applies to population as they reach K.
23
Q
Logistic growth Model
A
dN/dt - rN (K-N)/K
- dN/dt: equals intrinsic rate of natural increase, adjusted for amount of available resources
- r: intrinsic rate of increase
- N: number of individuals in population
- Plot N versus t, and you get a sigmoidal growth curve
24
Q
Ecological Footprint
A
- measures the amount of biologically productive land and sea area an individual, a region, all of humanity, or a human activity that compete for biologically productive space
- amount of productive land required to support an individual at the standard of living of a particular population through the course of his/her life
25
R/K Selection Theory
Combinations of traits in an organism that trade-off between quantity and quality of offspring.
26
Species with a large impact
1. Dominant Species: most abundant
2. Keystone Species: most influential with respect to trophic levels
3. Foundation Species: allows other species to inhabit an area by altering the environment
27
Community Ecology
The study of interacting populations of species living within a particular area or habitat.
28
Intraspecific Competition
Competition within a species.
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Interspecific Competition
Competition between species.
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Interference Competition
Direct, physical interactions over resources.
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Exploitative Competition
Interactive indirectly by consuming same resources.
32
Competitive Exclusion Principle
Two species cannot occupy the same niche in a habitat.
- different species cannot coexist in a community if they're competing for all the same resources
33
Niche
Total range of conditions under which an individual (or population) lives and replaces itself.
34
Realized Niche
Actual set of conditions under which an organism exists.
35
Fundamental Niche
Entire set of optimal conditions under which an organismic unit can live and replace itself.
36
Resource Partitioning
Among similar species occupying same geographical area.
- result of natural selection
37
Character Displacement
- differences in morphology between sympatric species
- role in adaptive radiation
38
Predation
Consumption of prey by its predators.
39
Chemical Defenses: Animals
- monarch butterfly caterpillars feed on milkweed and dogbane families
- incorporate cardiac glycosides from plants
- birds get sick when they eat monarchs
40
Defense Against Predation
- strawberry poison dart frog uses aposematic coloration to warn predators of their poison
- striped skunk uses aposematic coloration to warn predators of the unpleasant odor it produces
41
Camouflaged or Cryptic Colored Animals
- nonpoisonous and blend with surroundings
- don't usually live in groups
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Mimicry - Batesian
Harmless species imitate warning signals of harmful species.
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Mimicry - Mullerian
Related or unrelated poisonous species that share a predator come to resemble one another's warning signals.
44
Symbiosis - Commensalism
One benefits and the other is just there.
- remora and shark
- pea crab and tube worm or mollusks
45
Symbiosis - Mutualism
Mutually beneficial.
- acacia trees and ants
- clown fish and anemone
- cleaner shrimp and fish
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Symbiosis - Parasitism
One species benefiting (parasite) while the other is not.
47
Endoparasites
Live within the body.
48
Ectoparasites
Live on surface of host.
49
Parasitodism
Deposit eggs on/in host.
50
Endosymbiont
Live inside another.
51
Ecosystem
- Biotic and abiotic
- all organisms and the environment in which they live and interact
52
Four main abiotic biogeochemical cycles
1. Water
2. Carbon
3. Nitrogen
4. Phosphorus
53
Biological Communities characterized by species
1. Richness: number present
2. Abundance: number of individuals per species
3. Relative abundance: how common or rare relative to others
4. Diversity: species richness and evenness of species' abundances
- community composition changes gradually across landscapes
54
Evapotranspiration (ET)
The release of water into the atmosphere as water vapor, by evaporation, transpiration, and respiration
55
Flow of energy in ecosystems
- never recycled
- must always be replenished
56
Energy exists:
- heat
- light
- chemical-bond energy
- motion
57
First law of thermodynamics
Energy is neither created nor destroyed; changes form.
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Second law of thermodynamics
Some chemical-bond or light energy converted to heat (entropy)
59
Earth is:
An open system for energy. Major source of energy → Sun
60
Trophic Levels
- group of organisms which occupy same level in food chain
- each level differs in nutritional relationship with primary energy source
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Autotrophs
- Primary producers
- Self-feeders
- Assemble inorganic precursors into the array of organic compounds of which they are made
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Heterotrophs
- Consumers
- Obtain organic compounds by consuming other organisms
- Animals that eat plants and other animals
63
Trophic Levels
- Primary producers: autotrophs
- Consumers: heterotrophs
- Herbivores: first consumer level
- Primary carnivores: eat herbivores
- Secondary carnivores: eat primary carnivores or herbivores
- Detritivores: eat decaying matter
- Decomposers: microbes that break up dead matter
64
Limiting Nutrients
Nutrients in shortest supply and put a limit on growth.
65
Limiting Nutrients for:
1. Terrestrial and aquatic ecosystems: Nitrogen and Phosphorus
2. Algal populations in about 1/3 of world's oceans: Iron
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Primary Productivity
The rate at which energy is converted by photosynthetic or chemosynthetic organisms into organic matter.
67
Gross Primary Production (GPP)
Rate at which primary producers incorporate energy from the sun.
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Net Primary Productivity (NNP)
Energy that remains in primary producers after respiration and heat loss.
69
Flow of energy in ecosystems
About 1% of incoming solar radiant energy is captured by primary producers per year in chemical bond energy.
- carry out respiration
- losses to heat
heterotrophs only have chemical-bond energy left in primary producers
70
Ten Percent Rule/Law
During transfer of energy down trophic level, only about 10% of energy is stored as biomass; that's all that's left available to next trophic level.
71
Number of trophic levels
- limited by energy availability
only about 1/1,000 of energy captured by photosynthesis passes through to secondary carnivores
