Deck 19: Population and Community Ecology

Question 1

Mark and recapture is a way that ecologists can estimate the size of a population in a community or ecosystem.A researcher team recently captured, tagged, and released 50 crows in one geographic region.Then over the next few months, they captured 200 crows, of which 5% were tagged from before.They conclude that the population of crows in this region is roughly_________.(Outcome #7a)

A)100,000
B)10,000
C)1000

Answer 1

C

Question 2

Choose the best definition of biosphere.(Outcome #7a)

A)all of the ecosystems on the planet
B)all of the communities in an ecosystem
C)all of the ecosystems in a biome

Answer 2

A

Question 3

The study of the interactions of living organisms with their environment is called what?

A)ecology
B)ethology
C)taxonomy

Answer 3

A

Question 4

Ecologists are chiefly concerned with the ________ and ________ of living things in the environment.(Outcome #7a)

A)ancestry, similarities
B)distribution, abundance
C)cells, molecules

Question 5

The Karner blue butterfly lays its eggs on wild lupine plants.When the larvae hatch, they feed exclusively on the wild lupine.A study of this interaction occurs at what level of ecology?

A)population ecology
B)ecosystem ecology
C)community ecology

Question 6

Designating a species a K-selected species means that the species likely exhibits which set of characteristics?

A)long gestation, small birth number, large offspring, late maturation
B)short gestation, large birth number, small offspring, early maturation
C)lays eggs instead of giving live birth, has short life span, type II survivorship curve

Question 7

The principle that states that two different species cannot occupy the same niche in a given habitat is called what?

A)Pauli exclusion
B)competitive exclusion
C)mutual exclusion

Question 8

The quantitative study of changes in populations is called what?

A)demography
B)democracy
C)archaeology

Question 9

Ecologists use a method of studying a particular population of animal within a community called "mark and recapture." A researcher captures, marks, and releases 40 red fox into a large community.He then collects 100 different red fox over the next year.If the recapture rate is 10%, what is a reasonable estimate of the red fox population size?

A)40
B)400
C)4000

Question 10

How is the mass of an individual organism generally related to the organism's population density?

A)inversely proportional
B)directly proportional
C)inversely exponential

Question 11

Select the best definition of the term demography.(Outcome #7b)

A)the statistical study of population dynamics
B)the statistical study of population characteristics
C)the qualitative study of ecosystem diversity

Question 12

Commensal symbiosis is an interaction between two species best described how?

A)One species benefits from the interaction at a cost to the other species.
B)Both species benefit from the interaction.
C)One species benefits from the interaction, and the other is unaffected.

Question 13

Members of the same species within a community are called what?

A)conspecifics
B)heterospecifics
C)homospecifics

Question 14

The American Bald Eagle was on the Endangered Species list for many years, the bird's numbers have rebounded considerably.Study of these birds occurs at what level?

A)ecosystem ecology
B)population ecology
C)community ecology

Question 15

Which of the three lists of levels of life below is specific to ecological investigation?

A)species, genus, family, order
B)molecules, organelles, organs, cells
C)organism, population, community, ecosystem

Question 16

Animal species that exhibit long gestation periods, give birth to relatively large offspring, and maintain population numbers close to the habitat carrying capacity are called _______ species.(Outcome #7b)

A)K-selected
B)r-selected
C)unselected

Question 17

Which of the following best represents the principles of organismal ecology?

A)The monarch butterfly exists as a caterpillar larval stage that only feeds on milkweeds, so the butterfly depends on milkweed populations to reproduce.
B)Milkweeds rely on monarch butterflies for pollination, so milkweeds will only grow where monarch butterflies exist.
C)Milkweeds produce glycoside toxins which keep monarchs and other pests from feeding on them.

Question 18

The monarch butterfly lays its eggs on milkweed plants, and the milkweed-monarch interaction illustrates the principles of organismal ecology.Why? (Outcomce #7a)

A)The milkweeds contain toxins that keep predators of the monarchs away from the eggs; once hatched, the larvae leave the milkweeds for nearby plants.
B)The monarchs fertilize the milkweed flowers, and the milkweed protects their eggs from wasps and bees.
C)The larvae that hatch feed exclusively on milkweed plants, so monarchs rely on the presence of milkweeds to reproduce.

Question 19

What are the two primary parameters used to describe a population within a given habitat at a given point in time?

A)population range and life expectancy
B)population size and density
C)population birth and death rates

Question 20

If a population exhibits a death rate that exceeds its birth rate, it is likely to ________.(Outcome #7b)

A)remain constant in size
B)increase in size
C)decrease in size

Question 21

With a typical predator and prey, when the prey population increases,

A)the predator population decreases
B)the predator population remains stable
C)the predator population increases

Question 22

The life table data for the Dall mountain sheep indicate that at age 7-8 years, 69 sheep per 1,000 sheep will die while 640 per 1,000 sheep will survive into the next year.What is the mortality rate (per 1,000) for this age group?

A)0.108
B)97.3
C)107.8

Question 23

The sage plant Salvia leucophylla secrets a chemical that inhibits the growth of other sage plants nearby.Considering this, what is the most likely pattern of dispersion one would find in the plant's natural habitat?

A)random
B)uniform
C)clumped

Question 24

A population-birds, for example-that experiences a roughly uniform mortality rate across its lifespan will typically exhibit what type of survivorship curve?

A)Type II, linear
B)Type I, convex
C)Type III, concave

Question 25

As the individual body size of an organism increases, the population density for this organism in a given habitat tends to _______.(Outcome #7b)

A)decrease exponentially
B)decrease proportionally
C)increase exponentially

Question 26

What can one infer from a relatively linear survivorship curve, and what organism generally exhibits this kind of survivorship curve?

A)the mortality rate is roughly uniform across the lifespan of this organism; birds
B)the mortality rate is higher for older members of this population; humans
C)the mortality rate is higher for younger members of this population; oak trees

Question 27

A field ecologist is studying a sage plant (Salvia leucophylla) that grows wild in Southern California.She notices the characteristic uniform dispersion of the plants in all of the quadrats she has mapped out.This dispersion pattern tends to occur because_______.(Outcome #7b)

A)this plant drops its relatively heavy seeds straight to the ground immediately around it
B)this plant secretes a chemical that inhibits the growth of nearby plants
C)this plant relies on wind to disperse it's relatively lightweight seeds

Question 28

All of the organisms living together in a particular habitat and their interactions with their non-living environment are called:

A)communities
B)ecosystems
C)populations