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Problem 1
Add labels to the figure that follows, which illustrates the interacting factors in a declining population that contribute to the extinction vortex.
Problem 2
Compare and contrast the species interactions of mutualism, predation, and competition.
Problem 3
A mass extinction
a. Is global in scale
b. Affects many different groups of organisms
c. Is caused only by human activity
d. A and B are correct
e. A, B, and C are correct
Problem 4
Current rates of species extinction appear to be approximately
a. Equal to
b. 10 times lower than
c. 10 times higher than
d. 50 to 100 times higher than
e. 1000 to 10,000 times higher than
Problem 5
According to the generalized species-area curve, when habitat is reduced to 50% of its original size, approximately
a. 10%
b. 25%
c. 50%
d. 90%
Problem 6
Which cause of extinction results from humans' direct use of a species?
a. Overexploitation
b. Habitat fragmentation
c. Pollution
d. Introduction of competitors or predators
e. Global warming
Problem 7
The web of life refers to the
a. Evolutionary relationships among living organisms
b. Connections between species in an ecosystem
c. Complicated nature of genetic variability
d. Flow of information from parent to child
e. Predatory effect of humans on the rest of the natural world
Problem 8
Which of the following is an example of a mutualistic relationship?
a. Moles catching and eating earthworms from the moles' underground tunnels
b. Cattails and reed canary grass growing together in wetland soils
c. Cleaner fish removing and eating parasites from the teeth of sharks
d. Colorado potato beetles consuming potato plant leaves
e. More than one of the above
Problem 9
The risks faced by small populations include
a. Erosion of genetic variability through genetic drift
b. Decreased fitness of individuals as a result of inbreeding
c. Increased risk of experiencing natural disasters
d. A and B are correct
e. A, B, and C are correct
Problem 10
One advantage of preserving more than one population of an endangered species at more than one location is
a. A lower risk of extinction of the entire species if a catastrophe strikes one location
b. Higher levels of inbreeding in each population
c. Higher rates of genetic drift in each population
d. Lower numbers of heterozygotes in each population
e. Higher rates of habitat fragmentation in the different locations
Problem 11
There are fewer lions in Africa's Serengeti than there are zebras. This is principally because
a. Zebras tend to drive off lions
b. Lions compete directly with cheetahs, whereas zebras do not have any competitors
c. Zebras have mutualists that increase their population, whereas lions do not
d. There is less energy available in zebras to support the lion population than there is in grass to support the zebras
e. Zebras are a keystone species, whereas lions are not
Problem 12
Most of the nutrients available for plant growth in an ecosystem are
a. Deposited in rain
b. Made available through the recycling of decomposers
c. Maintained within that ecosystem over time
d. B and C are correct
e. A, B, and C are correct