principles of ecology final practice questions

the intermediate disturbance hypothesis suggests that:

a. maximum biodiversity occurs at high levels of disturbance

b. low levels of disturbance maximize biodiversity

c. moderate levels of disturbance support the highest biodiversity

d. ecosystems are stable regardless of the disturbance levels

c. moderate levels of disturbance support the highest biodiversity

what type of species are typically the first to colonize a newly disturbed habitat?

a. k-selected species

b. climax species

c. pioneer species

d. intermediate species

c. pioneer species

what does the miyawaki method aim to achieve in urban reforestation?

a. slow tree growth over centuries

b. replace native species with non-native ones

c. create dense microforests with rapid biodiversity growth

d. reduce tree cover in urban areas

c. create dense microforests with rapid biodiversity growth

T/F: keystone species exert a disproportionately large effect on ecosystem structure and function

true

T/F: biomagnification leads to a decrease in toxic substance concentration as it moves up the food chain

false, toxins accumulate in higher concentrations at hight trophic levels

T/F: the inhibition model of succession suggests that earlier species prevent the establishment of later species until they die

true

Link the decline of sea otters to the destruction of kelp forests

sea otters decline due to hunting orcas --> sea urchin pops increase (their prey) --> urchins overgraze kelp foerests --> los of kelp removes habitat for many marine species --> collapse of kelp forest ecosystems

which of the following is an example of secondary succession?

a. the colonization of volcanic rock by lichens

b. the development of a forest after a wildfire

c. the formation of new coral reefs in deep ocean regions

d. the creation of sand dunes on a coastline

b. the development of a forest after wildfire

what ecological process explains why coral reefs in Kaneohe Bay recovered after sewage was diverted offshore?

a. competitive exclusion

b. phase shfit

c. biomagnification

d. habitat fragmentation

b. phase shift

compare and contrast autogenic and allogenic succession

both processes shape community structure but differ in how they do so. autogenic succession is driven by biotic factors within the community (ex: species interactions). in contrast, allogenic succession is influenced by external abiotic factors (ex: climate, disturbance, or nutrient shifts)

T/F: in an energy pyramid, energy is evenly distributed across all trophic levels

false

T/F: coral bleaching occurs when corals expel their zooxanthellae due to heat stress

true

what is a key challenge that we discussed that is faced by urban reforestation efforts?

a. lack of community interest

b. competition for land and resources

c. excessive tree growth

d. complete elimination of pollution

b. competition for land and resources

which of the following is NOT a characteristic of an r-selected species?

a. high reproductive rate

b. short lifespan

c. strong parental care

d. rapid population growth

c. strong parental care

in trophic cascades, the removal of a top predator often leads to:

a. increased herbivore populations and decreased primary producers

b. decreased herbivore populations and increased primary producers

c. increased primary producer populations and increased herbivore populations

d. no significant changes in lower trophic levels

a. increased herbivore populations and decreased primary producers

define population

A group of the same species living in the same place at the same time

define system

interconnected sets of elements that are coherently organized in a way that achieves something

which has more dynamic seasonal light exposure: a tropical rainforest or a temperate deciduous forest?

temperate deciduous forest

which habitat generally supports a more complex food chain: polar bay or tropical estuary>

tropical estuary

which habitat would a ruderal species most likely be found in: hot desert or disturbance-prone grassland?

Disturbance prone grassland

all else equal, which habitat would recover faster via succession: a tropical forest after a volcanic eruption or a sub-alpine forest after a large fire?

sub-alpine forest after a large fire

link a deadly strain of canine parvovirus (causes dehydration and death in canines) introduced into the Isle Royale National park in Michigan by tourists' dogs to a 50% decline in songbird biodiversity in Isle Royale National Park

1. Wolf population contracts the virus and declines

2. Deer population explodes and leads to a decrease in plant biomass

3. Lack of plant biomass means less healthy soil

4. No healthy soil, and less plants means insect population decreases, leading to less food for songbirds

what factors distinguish the realized vs fundamental range of a species?

behavioral, dispersal, resources, competitors, and abiotic factors

what 3 things must all species do to continue existing?

survive, thrive, and reproduce

how do plate tectonics influence biodiversity?

plate movement create geographic barriers, leading to species isolation, divergence, and speciation

what is the difference between allopatric and sympatric speciation?

allopatric speciation occurs due to physical separation of populations, while sympatric speciation happens without a physical barrier, often through genetic changes or behavioral shifts

explain the role of zooxanthellae in coral reefs

Form a symbiotic relationship with the coral reefs; increasing ocean temperatures bleach them and lead to the deaths of coral

explain the role of zooxanthellae in coral reefs

zooxanthellae are photosynthetic symbionts that provide corals with nutrients and energy, while corals offer them shelter and CO2 for photosynthesis

what is the difference between a fundamental and realized niche?

a fundamental niche is the full range of conditions a species can occupy while the realized niche is where it actually exists due to competition and other factors

difference between climate and weather

weather is short term condition of the atmosphere; weather is the average trend of the weather pattern over a long period of time

what is the difference betwen migration and dispersal?

migration is the cyclical pattern/movement of species through their environment, such as eels or turtles moving between their breeding and feeding grounds. dispersal is a one-way trip or permanent movement of individuals form the adult habitat to the offspring habitat

what are the four forces of evolution?

gene flow, natural selection, mutation, and genetic drift

T/F: according to the coriolis effect, an object deflected from the northern hemisphere will move towards the left

false, objects deflected from the northern hemisphere will move to the right

what are the six levels of ecological organization?

organism --> population --> community --> ecosystem --> landscape --> biosphere

how do rats reshape coral reefs?

when rats are introduced to some islands they prey upon eggs and chicks of birds, decreasing the bird count and diversity. Now there are less birds foraging at sea so less nitrogen is deposited in the near-shore habitat (nitrogen deposits occur through bird feces). marine algae then have less nutrients to grow and the number of algae-eaitng fish (ex. damselfish) declines along with the coral health

what are four things to consider when defining evolution and how would we then define evolution?:

we must consider genetic material, changes, population, and time. with all four, we define evolution as change ni gene frequencies within a species population over time

what two words came together to make the term ecology. define those words and explain how they correlate to the definition of ecology

biology - the scientific study of living organisms

economics - the study of systems and interactions between systems

- they relate to the definition of ecology because ecology is defined as the study of the relationships/interactions among living organisms and their environment

differentiate between acclimation and adaptation

acclimation: short-term physiological adjustments organisms make in response to environmental changes

adaptation: long-term evolutionary changes in physiology over generations

differentiate between endotherms and ectotherms

ectotherms: organisms that depend on external heat sources for temperature regulations

endotherms: organisms that generate internal heat through metabolic processes, regardless of external conditions

What does He mean in the heat storage equation (HS = Hm ± Hcd ± Hcv ± Hr - He)?

a. heat of exhalation

b. heat of exchange

c. the heat of evapotranspiration

d. heat of evaporation

d. heat of evaporation

what physiological features do organisms use for temperature regulation? (select all that apply)

a. bradycardia

b. countercurrent exchange

c. vasoconstriction

d. sweating

e. insulation

Bradycardia, countercurrent exchange, vasoconstriction and sweating

how does bradycardia (slowing heart rate) help animals conserve heat?

a. it raises blood pressure, which allows for more blood flow and more heat

b. it keeps blood to the core which means less heat is lost to the environment

c. it means less blood to the outer parts of the body and causes shivering

d. it means more blood to the skin allowing for a higher body temperature

b. it keeps blood to the core which means less heat is lost to the environment

T/F: poikilotherms can only survive in narrow temperature ranges

False, that is stenotherms

what kind of species interaction occurs when Dr. Willette's former bees collect pollen while pollinating flowers?

a. parasitism

b. mutualism

c. commensalism

d. competition

b. mutualism

which of the following is NOT a characteristic of prokaryotic cells?

a. lack of a nucleus

b. presence of membrane-bound organelles

c. single circular chromosome

d. cell wall in most species

b. presence of membrane-bound organelles

T/F: in terms of trade-offs in organism performance, fecundity refers to reproductive sucess?

True

how do plants acclimate to seasonal temperature changes?

a. through short-term physiological adjustments

b. by undergoing genetic adaptation

c. by migrating to warmer areas

d. by increasing their water intake

a. through short-term physiological adjustments

which of the following is NOT an example of homeostasis?

a. regulating blood sugar levels through insulin and glucagon

b. maintaining a stable body temperature in mammals

c. fish developing antifreeze proteins over generations to survive cold waters

d. the kidney balancing salt and water levels in the body

c. fish developing antifreeze proteins over generations to survive cold waters

a barnacle attaching to a whale and gaining transportation without affecting the whale is an example of?

a. parasitism

b. compeition

c. commensalism

d. mutualism

c. commensalism

match the terms with the correct def:

1. ecology

2. population

3. community

4. ecosystem

5. biosphere

6. Niché

7. natural selection

8. genetic drift

9. hardy-weinberg equilibrium

10. sympatric speciation

a) the study of interactions between organisms and their environment

b) a group of individuals of the same species living in the same area

c) all the organisms living in an area and interacting with each other

d) a biological community plus its physical environment

e) the global sum of all ecosystems on Earth

f) the role and position a species has in its environment

g) process by which individuals with advantageous traits survive and reproduce

h) random changes in allele frequencies in small populations due to chance

i) a popoulation remains genetically stable if no evolution occurs

j) new species arise without a physical barrier, often due to genetic divergence

1 - A

2 - B

3 - C

4 - D

5 - E

6 - F

7 - G

8 - H

9 - I

10 - J

what type of species interaction occurs when two species compete for the same food resource?

a. mutualism

b. commensalism

c. competition

d. parasitism

c. competition

keystone species play an important role in ecosystems because:

a. they are the most abundant species

b. they have a disproportionately large effect on their environment

c. they always act as predators

d. they do not interact with other species

b. they have a disproportionately large effect on their environment

what is carrying capacity (K)?

a. the max number of individuals an environment can support

b. the total number of births per year in a population

c. the minimum population size needed for survival

d. the number of individuals that migrate each year

a. the max number of individuals an environment can support

which type of survivorship curve is characterized by high juvenile mortality but increased survival for adults?

a. type I

b. type II

c. type III

d. logistic

c. type III

a species that produces many offspring with little parental care typically exhibits what type of reproductive strategy?

a. k-selected

b. r-selected

c. logistic-selected

d. carrying capacity selected

b. r-selected

what is the difference between intraspecific competition and interspecific competition?

intraspecific competition is competition for resources of the same species, and interspecific competition is between individuals of different species

early in this course, we discussed three things all species require to continue existing as a species. which of the following is NOT one of those things?:

a. survive

b. thrive

c. arrive

d. reproduce

c. arrive

________ _______ occurs due to the physical or geographic separation of population, while _____ ______ occurs without a physical or geographical separation of the population:

a. sympatric speciation; allopatric speciation

b. natural selection; vicariance

c. allopatric speciation; sympatric speciaiton

d. gene flow; vicariance

c. allopatric speciation; sympatric speciation

______ is the long term patterns and trends of precipitation + temperature in an area, whereas ____ are the short-term (day-to-day) conditions in precipitation + temperature.

a. weather, ecosystem

b. weather, micro-climate

c. climate, weather

d. climate, micro-climate

c. climate, weather

which of the following is not one of the seven levels of ecological organization, as presented in Principles of Ecology?

a. organ

b. organism

c. interaction

d. landscape

a. organ

evolution is defined as the change in _____ within _____ over time.

a. weather patterns; two ecosystems

b. two populations; one ecosystem

c. allelic frequency; an ecosystem

d. allelic frequencies; a population

d. allelic frequencies; a population

recall the "methods in field sampling" lab we had in week 1. what is the name of the tool we used to estimate percent cover of plants on the green roof?

a. quadrat

b. transect line

c. calipers

d. sand corer

a. quadrat

which of the following is NOT an assumption of the Hardy-Weinberg equilibrium model?

a. no gene flow

b. small population size

c. no migration

d. random mating

b. small population size

Historically Florida panthers numbered in the thousands in the southeastern region of the United States, but today there are reported to be less than 200 in the wild. The genetic diversity of the remaining panthers is substantially lower than it was historically; a condition illustrated in high frequency of Feline Immunodeficiency Virus and Puma Lentivirus resulting from inbreeding. Which evolutionary process best explains the current genetic diversity of the Florida panther?

a. natural selection

b. allopatric speciation

c. genetic drift via founder's effect

d. genetic drift via bottleneck

d. genetic drift via bottleneck

Considering Mendelian inheritance, say you cross a pair of pea plants with the genotypes YY and

yy. Y represents the dominant color trait yellow, y represents the recessive color trait green. What

percentage of the resulting offspring will be heterozygotes?

a. 0%

b. 25%

c. 50%

d. 100%

d. 100%

T/F: vicariance is the precursor to allopatric speciation

true

T/F: heritability decreases with environmental vicariance

true

T/F: open populations are those without barriers to migration

true

T/F: evolution acts at the scale of the individual, where was adaption acts at the scale of the poulation

false

T/F: in experimental design, replicates are included to account for the inherent variability within the experiment, thus giving increased validity to the results.

true

distinguish between a balancing (negative feedback) loop and reinforcing (positive feedback) loop

positive feedback enhances or amplifies a change that moves the system away from homeostasis/set point; negative feedback buffers changes that occur after a stimulus pushes a system away from homeostasis/set point, bringing it back to said set point

distinguish between dynamic equilibrium and resiliency

dynamic equilibrium refers to a system where the system maintains a relatively stable balance through adjustment, whereas resilience describes the system's ability to recover from disruption (even a significant disturbance) back to a functional state

distinguish between migration and dispersal

migration is the cyclical movement of an organism between distinct regions for different purposes over its lifetime, dispersal is the one-directional movement of an organism as one point in its lifetime (e.g. larval dispersal, seed dispersal)

T/F: trade-offs must be made at the individual level in response to fecundity, growth, and longevity

True

T/F: ectotherms derive body temperature from internal heat production

false

T/F: fur, blubber, and hibernation are all examples of anatomical features of animals to maintain homeostasis

false

T/F: when N=(1/2)K under logistic growth, the population growth is the slowest

False

T/F: competitive exclusion principle states two species with identical needs cannot co-exist indefinitely

true

wildebeest in the Serengeti plains of africa have historically been kept at low numbers by a disease called rinderprest. wildebeest are a major grazer of the grasses in the serengeti. in the 1960s, a campaign to eradicate the rinderpest disease in the area was successful, leading to greatly increased wildebeest numbers. what effect would you predict for grasses as a result of rinderpest eradication?

a. fewer grasses

b. more grasses

c. at first more grasses, and then fewer over time

d. no change

consider the scenario from the previous question. the more grasses there are, the more fires sweep through the serengeti, affecting both grasses and trees growing in the plains. with the understanding that the trees are fire-resistant, what indirect effect would likely happen for trees as a result of rinderpest eradication?

a. fewer trees

b. more trees

c. loss of all trees

d. no change

Q1: a. fewer grasses

Q2: b. more trees

during our catalina trip, we were introduced to the sub-field of nocturnal ecology. which of the following is NOT a benefit specific for a nocturnal animal species?

a. temporal niche partitioning

b. spatial niche partitioning

c. decreased water loss

d. easier to hunt prey

b. spatial niche partitioning

In the video 'How wolves change rivers' (watched in lecture), the extirpation of grey wolves from

Yellowstone National Park released deer from predation pressure and resulted in a boom in the deer population. The increase in deer caused a decline in aspen and willow trees, which subsequently caused the destabilization of the riverbanks and decline in a wide diversity of tree-dwelling bird species. This change in the food webs is an example of which of these:

a. supply-side cascade

b. bottom-up cascade

c. trophic cascade

d. behavioral cascade

c. trophic cascade

A plant living in an environment with a low frequency of disturbances and low level of stress fits into which

plant life history category?

a. ruderal

b. competitive

c. stress tolerant

d. neutral

b. competitive

In the Lotka-Volterra model for cyclic predator-prey interactions, there is a lag period between the two

interacting populations (lines). Which line represents the predator and why?

a. the dotted line; predators are the controlling factor in this model

b. The solid line; there is a delay in the time it takes for a predator to reproduce

c. The dotted line; predators are inefficient hunters and thus increase first

d. The solid line; density-dependent limitations due to outside factors

b. The solid line; there is a delay in the time it takes for a predator to reproduce

From our Catalina trip's kayak activity, what oceanographic process fuels the high productivity of kelp

forest along the western coast of North America?

a. ocean gyres

b. coriolis effect

c. upwelling

d. downwelling

c. upwelling

During our Saturday afternoon activity around Wrigley marine station, what group of organisms did we dig

for and describe based on number of legs, body length, and description?

a. decomposers

b. primary producers

c. primary consumers

d. worms

a. decomposers

From our Catalina trip, which of the following animals that we saw (collectively as a class) is a non-native

species to the island?

a. raven

b. california spiny lobster

c. milk snail

d. foundational species

c. milk snail