Reorder the following:

• Thin soil accumulates

• New land is formed by volcanic lava hardening into rock

• A mature community of plants and animals develops

• Birds carry plant seeds to the new soil.

• Lichens and moss grow, transforming the rock to soil

Where is secondary succession most likely to occur?

• After a natural disaster like a forest fire, where soil remains

• After mining, when soil and resources are removed

• A prairie with an existing ecosystem

• An area where new soil has formed

How are predator-prey and parasite-host relationships similar?

• No animals are harmed in either

• No animals benefit from either

• One member of each relationship is harmed

• Both animals are helped in both

What's true about the effect of the Exxon Valdez oil spill? Choose 3.

• Different species are affected differently and therefore recover at different rates.

• The herring population was so severely affected that it had not recovered by 2014.

• The Kittlittz's murrelet recovered within 7 years.

• The Common Murre has not yet recovered due to its habitat and prey not recovering.

• Some populations, like the bald eagle, were not affected much and recovered very quickly, within 7 years.

River otters prey on organisms found in the rocky intertidal region, as well as in rivers (not shown). Sea otters prey on clams and mussels. Which of the following inferences is supported?

• River otters recovered faster because their prey were eliminated by the oil spill.

• River otters recovered faster than sea otters because their prey recovered faster.

• Sea otters recovered faster than river otters because their prey recovered faster.

• River otters recovered faster because their subtidal communities recovered faster than the rocky intertidal.

Match the following examples to the term.

• One species hunts and consumes another

• Mutualism

• One benefits, the other is unaffected

• Commensalism

• One species benefits at the expense of the other

• Parasite/Host

• Both species benefit from the relationship

• Predator/Prey

​ (a)   extinction occurs as ​ (b)   species dies out over time, whereas a ​ (c)   extinction occurs when ​ (d)   species die out all at once.

• Background
• one
• mass
• many

An organism's role within its ecosystem is a _____

Grey wolves are considered a keystone species within Yellowstone National Park. They are also a predator of elk. Elk tend to eat willow trees, which are vital to holding streambanks and preventing erosion. What is the likeliest long term effect of removing the grey wolf from Yellowstone?

• An increase in the number of elk calves born every spring.

• Erosion. Elk that have larger numbers will eat more willows. The willows will then not hold the streambanks.

• A decrease in the number of bears as wolves are responsible for elk kills and bears depend on them to scavenge from.

• An increase in the number of tree species as increased grazing pressure creates new and different species.

The introduction of a non-native, or ​ (a)   species, like the Zebra mussel, is problematic because these species may ​ (b)   with native species and reduce ​ (c)   .

• invasive
• compete
• biodiversity
• reproduce