Unit 2 Vocab Test

When a large oil spill occurs, the cleanup cost, health impacts, and loss of recreational use all highlight the economic value of natural systems that purify water and maintain air quality. Which concept describes the benefits provided by natural ecosystems?

Ecosystem Services

Tropical rainforests possess a wide variety of species occupying numerous ecological niches, whereas tundra ecosystems have fewer species overall. Which measure of biodiversity is being compared here?

Species Richness

A species of sea otter in the Pacific Northwest indirectly supports kelp forest biodiversity by preying on sea urchins that would otherwise overgraze kelp. When sea otters decline, the entire community structure collapses. What type of species role does the sea otter represent?

Keystone Species

A population of insects exposed to pesticide over multiple generations evolves resistance, while individuals lacking resistance genes die off. Which overarching process best explains this change in population traits?

Evolution

In a wetland ecosystem, mayflies and amphibians are highly sensitive to changes in water quality. Their disappearance from a stream signals pollution or oxygen depletion. What type of species are these organisms?

Indicator Species

Zebra mussels introduced into North American freshwater systems outcompete native mussels for food and space, disrupting ecosystem balance and decreasing native biodiversity. Which term best describes the zebra mussels?

Invasive Species

A small forest is divided by the construction of highways and residential neighborhoods, isolating populations of organisms and limiting gene flow between them. Over time, some populations become genetically distinct. Which process is primarily occurring?

Habitat Fragmentation

A raccoon can thrive in forests, urban areas, and coastal habitats due to its ability to eat a variety of foods and adapt to diverse conditions. What ecological category does the raccoon represent?

Generalist species

Larger islands located closer to the mainland tend to support greater biodiversity compared to smaller, isolated islands due to higher immigration and lower extinction rates. Which ecological theory explains this pattern?

Island Biogeography

After a hurricane destroys much of a coastal ecosystem, hardy grasses and shrubs rapidly colonize the disturbed area before trees and other complex species re-establish over time. These early colonizers are known as:

Pioneer Species

A population of cheetahs experienced a severe decline due to a past ice age event that left only a few survivors. As a result, current cheetahs have extremely low genetic variation, making them more vulnerable to disease. What concept explains this reduced genetic diversity?

Bottleneck

Following a volcanic eruption, an uninhabited island begins to show the first signs of plant growth. Lichens and mosses establish themselves on the bare rock, breaking it down into soil that allows grasses and shrubs to later colonize the area. Which ecological process is being described?

Succession

Beetle species in a tropical rainforest show variations in coloration and behavior. Over generations, natural pressures favor those with camouflage that enhances survival, leading to a gradual increase in that trait in the population. Which biological mechanism best describes this scenario?

Natural Selection

Humans clear forests, introduce pollutants, and release greenhouse gases, altering natural cycles and reducing biodiversity on a global scale. What term best describes these human-caused impacts?

Anthropogenic

Coral reef fish often have very specific diet requirements and habitat conditions. When environmental changes occur, these fish populations decline rapidly, while more adaptable species persist. How would you classify these coral reef fish?

Specialist species