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76 terms

Ebio test 4

STUDY
PLAY
Ecology is:

A) the environment
B) the study of plants and animals
C) the science of conservation
D) the study of interactions between organisms and the environment
E) a "green" philosophy
D) the study of interactions between organisms and the environment
What does biotic environment mean
the living component, all of the organisms (competition, predation, paratism, etc.)
what does abiotic environment mean
Nonliving; referring to physical and chemical properties of an environment. (temperature, light, water, nutrients, shelter etc.)
what is the ecological scope hierarchy
1. individual
2. population
3. community
4. ecosystem
5. landscape
6. biosphere
Which of the following levels of organization is arranged in the correct sequence from most to least inclusive?

A) community, ecosystem, individual, population
B) ecosystem, community, population, individual
C) population, ecosystem, individual, community
D) individual, population, community, ecosystem
E) individual, community, population, ecosystem
B) ecosystem, community, population, individual
Which of the following are biotic factors that could determine where an organism is found?
A) sunlight and water for photosynthesis
B) nutrients for growth
C) viral diseases, parasites
D) water for animals to drink
E) all of the above
C) viral diseases, parasites
Behavior is part of animals __________
Behavior is part of animals phenotype
Behavior is essential to ____________ and __________ and thus ____________
Behavior is essential to reproduction and survival and thus natural selection
explain the proximate cause of behavior
HOW (the immediate stimulus and mechanism)
explain the ultimate cause of behavior
WHY (Evolutionary significance; via survival and ultimately reproduction)
A female cat in heat urinates more often and in many places. Male cats congregate near the urine deposits and fight with each other. Which of the following is a proximate cause of this behavior of increased urination?

A) It will stimulate male cats to mate with her

B) It announces to males that she is in heat

C) Female cats that did this in the past attracted more mates

D) It is a result of hormonal changes associated with her reproductive cycle

E) It will stimulate male cats to fight with each other so that only the best male mates with her
D) It is a result of hormonal changes associated with her reproductive cycle
A kangaroo rat instinctively reacts to the sound of a rattlesnake by executing an escape jump. Which is the ultimate cause?

A) The sound of the rattlesnake. B) To avoid being killed.
C) Fear of rattlesnakes.
D) To produce more offspring.
E) Aggression.
D) To produce more offspring.
what is learning
Learning: modification of behavior based on specific experiences
As we discussed, the distribution and abundance of red kangaroos in Australia is negatively correlated with rainfall. That is, kangaroos are more abundant where there is less rain and absent where rain is plentiful. What can we conclude from this pattern?

A) Rainfall determines the distribution of red kangaroos.
B) Nothing, both rainfall and interactions (competition, predation) with other organisms that depend on rain could determine the distribution of red kangaroos.
C) Kangaroos need water to survive.
D) Latitude determines the distribution of red kangaroos.
B) Nothing, both rainfall and interactions (competition, predation) with other organisms that depend on rain could determine the distribution of red kangaroos.
The two behaviors that affect fitness directly are...
The two behaviors that affect fitness directly are foraging and mating
What is foraging
Foraging: behavior associated with recognizing, searching for, capturing, and consuming food
what is the optimal foraging theory
Optimal foraging theory:
foraging behavior is a compromise between benefits of nutrition and costs of obtaining food
What further study is needed to show that dropping whelks from a height of 5.23 m is a behavior that arose directly from evolution by natural selection?

A) The behavior is heritable - i.e. it has an innate genetic component.
B) Adult crows teach the young crows to fly to that height, thus passing the behavior on to the next generation.
A) The behavior is heritable - i.e. it has an innate genetic component.
Variation in a ______ dictates foraging behavior in the larvae
Variation in a gene dictates foraging behavior in the larvae
At birth, baby kangaroos climb into their mother's pouch and begin to nurse. Is this behavior
A) innate
B) learned
C) migration
D) ultimate
E) proximate
A) innate
(intersexual selection):
Female choice (intersexual selection): may play central role in evolution of male behavior and anatomy in most species
(intrasexual selection):
Male competition (intrasexual selection): evolution of alternative male mating behavior and morphology in most species
what is population ecology
Analyzes factors that determine population size (how and why it changes in space and time).
what are some examples of population ecology applications
Endangered species
Managed populations (e.g. fisheries, hunting)
Pest control (e.g. agriculture)
Humans (demography, disease outbreaks)
what is the change in population size equation
(b+I)-(d+e)=n
Unlimited growth ...
Unlimited growth does not occur for long in nature
All species have capacity for ...
All species have capacity for unlimited growth when resources are abundant
A small population of white-footed mice has the same per capita rate of increase (r) as a large population. If both populations have unlimited growth,

A) the large population will add more individuals per unit time.
B) the small population will add more individuals per unit time.
C) the two populations will add equal numbers of individuals per unit time.
D) each individual in the smaller population will give birth to fewer offspring per unit time.
E) the growth trajectories of the two populations will proceed in opposite directions.
A) the large population will add more individuals per unit time.
what is Carrying capacity (K)
Carrying capacity (K) is the maximum population size the environment can support
What are density-independent factos
one in which the birth rates or the death rates do not change with population density but are affected by other factors e.g., weather
what are density dependent factors
Birth or death rates change with population density (e.g competition for resources - intraspecific competition)
Name four density dependent factors that determine carrying capacity (K)
competition
territoriality
disease
predation
in density dependent factors explain competition
Competition for resources like food (animals) or nutrients (plants).
in density dependent factors explain territoriality
Territoriality - competition for nesting sites
in density dependent factors explain disease
Disease - diseases spread more easily when population density is high.
in density dependent factors explain predation
Predation - large populations more likely to be preyed on.
Where does density dependence occur in the life cycle of the mountain ash?

A) Seed stage because there are so many seeds there is strong competition for water to germinate.
B) Sapling tree stage because there is intense competition for light and only the best competitors survive.
C) Mature tree stage because fire can only occur at the highest tree densities.
B) Sapling tree stage because there is intense competition for light and only the best competitors survive.
Which of the following (A-E) does not contribute to density dependent regulation of populations?

A. Competition for nesting sites
B. drought stress
C. competition for available water
D. competition for nutrients
E. disease
B. drought stress
A small population of white-footed mice has the same per capita rate of increase (r) as a large population. If both populations have unlimited growth,

A) the large population will add more individuals per unit time.
B) the small population will add more individuals per unit time.
C) the two populations will add equal numbers of individuals per unit time.
D) each individual in the smaller population will give birth to fewer offspring per unit time.
E) the growth trajectories of the two populations will proceed in opposite directions.
A) the large population will add more individuals per unit time.
what is the demographic transition
DEMOGRAPHIC TRANSITION

As a country develops, birth and mortality rates decline
Mortality rates decline first (better healthcare)
Birth rates decline slower as people realize they need fewer children as "insurance"
People decide to have fewer children in developed nations
What are four density dependent mechanisms for humans
Food
Space
Nonrenewable resources (e.g. metals)
Buildup of wastes
What effect does the
following pattern of
births and deaths
have on a population?


A) extinction
B) exponential growth
C) density-dependent regulation
D) the population size will be the average of births and deaths
E) fluctuating population size
B) exponential growth
What is a community
A community is a group of different species in an area living close enough for potential interactions
what is community ecology
Community ecology examines how interactions between species affect community structure.
what is species richness
Species richness: the number of species present
what is relative abundance
Relative abundance: proportion of each species present
what is species composition
Species composition:
which species are present?
what is interspecific competition:
Interspecific competition: when individuals of different species compete for a particular resource that is in short supply
what is the competitive exclusion principle
Competitive exclusion principle: only the best competitor survives; poorer competitors are eliminated
What is an ecolofical niche
Ecological niche: sum total of a species' use of abiotic and biotic resources (species' ecological role)
List 4 dimensions that are included in a niche
1. temperature tolerance
2. perch sites
3. time of activity
4. diet
Two species cannot coexist in a community if...
Two species cannot coexist in a community if their niches are identical
what is the difference between realized niche and fundamental niche
realized niche is the niche that a species has fallen into and are currently in.
A fundamental niche is the the niche that a species has the ability to survive in
Other observations showed that Balanus cannot survive high on the rocks because it dries out during low tides. Given this observation, how does Balanus's realized niche compare with its fundamental niche?

A) Wetter
B) Drier
C) Larger
D) Smaller
E) Same
E) Same
What is the energetic hypothesis
Length of food chain limited by inefficiency of energy transfer along chain
What is the dynamic stability hypothesis
Long food chains are less stable than short chains
Periodic local extinctions of top predators, due to population fluctuations at lower trophic levels
Predicts that food chains will be shorter in unpredictable environments
All of the following phrases could characterize a community except

A) interacting individuals.
B) interacting species.
C) species diversity.
D) boundaries.
E) single species.
E) single species.
In a tide pool, the species richness of invertebrates was reduced from 15 to eight after one species was removed. The species removed was likely a(n)

A) autotroph.
B) keystone species.
C) herbivore.
D) dominant species.
E) ecosystem engineer.
B) keystone species.
Two barnacles, Balanus and Chthamalus, can both survive on the lower rocks just above the low-tide line on the Scottish coast, but only Balanus actually does so, with Chthamalus adopting a higher zone. Which of the following best accounts for this niche separation?

A) competitive exclusion
B) predation of Chthamalus by Balanus
C) cooperative displacement
D) primary succession
E) mutualism
A) competitive exclusion
What is a disturbance
An event, such as a storm, fire, flood, drought, overgrazing, or human activity, that changes a community, removes organisms from it, and alters resource availability.
What is succession
Disturbed area re/colonized by species, which are gradually replaced by other species, which are also gradually replaced by other species
What is facilitation
an important process. early species create conditions for later ones (e.g., soil, nutrients)
Explain the four usual steps of primary succession
1. Lifeless area with little or no soil (disturbance is severe; retreating glacier, volcanic eruption)

2. Lichens and mosses (windblown spores) often first colonists

3. Soil develops, grasses shrubs and trees sprout

4. Eventually area is colonized by plants that become the community's main form of vegetation
What is secondary succession
Existing community cleared by a disturbance and leaves soil intact (disturbance not severe)
which is faster primary or secondary succession?
Secondary succession
What are the most limiting items about an aquatic ecosystem
light and nutrients
what are the two major components to nutrients in an aquatic system
nitrogen and phosphorous
What are the most limiting items about a terrestrial ecosystem
temperature, moisture, (and nutrients)
what is actual evapotranspiration
is the water annually transpired by plants and evaporated from a landscape
Choose the most correct answer. The ecosystems that contrivute least to net primary production :

A) Have high actual evapotranspiration rates
B) Are the ocean and temperate forests
C) Are warm and wet
D) Are cold and dry
E) Tend to be in the tropics
D) Are cold and dry
What is climate
Temperature, precipitation, humidity, wind, etc of an area characterized over a long period of time. Contrast "weather": the condition of these variables at one time.
What is climate change
Climate change occurs when the climate changes in time (e.g., winter months get warmer) or space (e.g., snow line moves up the mountainside).
What are biomes
major terrestrial ecosystems, defined based on their plant communities and abiotic characteristics
Climate largely determines the nature and locations of _________
biomes
What is global climate
Global climate refers to climate conditions averaged over the Earth's surface (i.e. the global average).
What determines global climate change
Climate results from a balance between the rate at which energy arrives at and leaves Earth