Approximately how many species are estimated to exist on Earth?
5–30 million
What factors influence a species' biotic potential?
Habitat requirements and reproductive rates
The logistic model of growth levels off at the ________.
Carrying capacity
Interspecific competition is:
The competition between species for the same resource
What are density-independent factors?
Factors that affect all populations regardless of size
An endangered species is in immediate jeopardy of:
Extinction throughout a large portion of its range
What are the "limits" that keep populations from increasing indefinitely called?
Limiting factors
What is natality in terms of population growth?
Addition of new individuals (birth rate)
A survivorship curve shows the probability of ______ for a given group or species.
survival
Would you rather be paid $5.00/hr for a 20-hour week, or a salary that starts at 1¢ the first hour and doubles each hour up to 20 hours?
1¢ doubling every hour = $10,485.00
A threatened species is at risk of becoming endangered:
At some point in the future
What are density-dependent factors?
Factors that have an increasing effect as the population increases
What does a population pyramid show?
A snapshot of the current population
Which form of isolation involves populations mating at different times or seasons?
Temporal isolation
R strategists reproduce ______.
Rapidly
Speciation occurs when:
The gene pools of two populations are separated and can no longer interbreed
What is the primary difference between linear and exponential growth?
Linear growth increases by a constant amount, while exponential growth increases by a constant rate
The logistic growth curve is also known as a(n) ________.
S curve
The Endangered Species Act of 1973 aims to:
Place international trade restrictions on threatened or endangered species
A gene pool is:
The combined genetic information for a particular population of organisms
Mechanical isolation occurs when:
The reproductive organs of two groups are no longer compatible
How does carrying capacity affect exponential growth?
It stabilizes growth
What type of curve has low fertility and high parental care?
Type 1 curve (humans and large mammals)
The principle of competitive exclusion states that:
Two species competing for the same resource cannot both have thriving populations
What weighs more a pound of cotton or a pound of rocks?
Neither, they both weigh a pound.