Biology Unit 4 Lesson 1 Self Check
A population of rodents is introduced on a remote island due to a shipwreck. Eventually, the population reaches the island's carrying capacity. At this point, birth rates are
A - Relatively Equal
A population of Warblers, a type of songbird, experiences a period of exponential growth. Which of these factors would be a density-dependent limiting factor that could decrease the carrying capacity of the ecosystem for this population of songbirds?
A - a competing species moves into the forest
Which of these abiotic factors would contribute to a clumped dispersion pattern in an ecosystem?
B - Limited Water, D - Limited Sunlight
A songbird has an equal chance of surviving at all stages of its life. According to the graph, which type of survivorship does the songbird exhibit?
B - Type II
A population of antelope has a negative population growth rate. Which of these conditions must also be true for the population growth rate to be negative?
C - Births + Immigrations < Deaths + Empigrations
A female salamander lays hundreds of eggs at a time. However, after hatching, few of the larvae survive to adulthood.
C - Type III
A population of deer is displaced by a massive flood in their habitat following a severe rainstorm. The flood is an example of
C - a density-independent limiting factor
What might cause exponential growth to occur only for a short period when a new species is introduced to a resource-filled environment?
Eventually, the growing population will consume all available resources, and the species may experience a population crash.
Describe three advantages an individual organism might have by living in a population with a clumped dispersal pattern.
Individuals do not have to move very much to find mates, organisms have better protection from predators, and there is more access to food resources.
A sourdough bread starter is a colony of yeast that bakers keep alive, sometimes for years. The bread is made by removing a portion of the colony, which is replaced by adding back and equal amount of water, sugar, and flour. Is the starter a model of exponential growth or logistic growth?
The bread starter is an example of logistic growth because the yeast has population growth that is a period of slow growth, followed by a period of exponential growth, followed by another period of almost no growth because of bakers taking some of the colony for bread.
How did the reintroduction of wolves change the Yellowstone ecosystem?
The reintroduction of wolves affected the Yellowstone ecosystem directly because wolves kept elk populations down, but also indirectly because elk populations decreasing can help populations of willows grow, giving beavers more food to eat which would increase their population too.
