WorksheetsKE REVIEW~ UNIT 8
Total questions: 20
Worksheet time: 5hrs 0mins
Which description is the best example of a population?
all of the red foxes in a forest
all of the red foxes in every forest
all of the organisms in a forest
all of the organisms in every forest
In Pennsylvania, a nonnative plant called stiltgrass out-competes native plants in many forest ecosystems. Which statement best describes how the spread of stiltgrass negatively affects native herbivores?
Stiltgrass stops the life cycles of native herbivores.
Stiltgrass reduces the size of the native plant populations.
Stiltgrass increases the flow of energy through the ecosystem.
Stiltgrass attracts other nonnative plants to the forest ecosystem.
Which energy transfer most likely occurs between organisms in the food web?
from owl to fox
from rabbit to fox
from sparrow to grass
from mouse to grasshopper
Most of the water on Earth is located in the oceans and has a salinity of about 3.5%. Which statement best explains why rain is fresh water and has a very low salinity?
When water precipitates from oceans, most of the salt remains in the oceans.
When water evaporates from oceans, most of the salt remains in the oceans.
When water precipitates from clouds, most of the salt remains in the clouds.
When water evaporates from clouds, most of the salt remains in the clouds.
Scientists observed that the populations of top-level consumers in a particular ecosystem were rapidly decreasing. Further studies revealed that there was also a decline in producer productivity. Which other changes did the scientists most likely observe in the ecosystem?
increased producer diversity
decreased population size at all levels
decreased primary consumer populations only
increased primary and secondary consumer diversity
A student listed characteristics of a classroom aquarium ecosystem. Which characteristic is a biotic component of the aquarium ecosystem?
The water temperature is 23°C.
The pH of the water is usually between 6.5 and 6.8.
The ammonia is controlled with a filter that uses two types of bacteria.
The lighting is supplied by natural sunlight and a fluorescent light bulb.
Which population description is most likely represented by the graph?
A population of birds quickly increases but then becomes stable due to limiting factors in the environment.
A population of mice slowly increases but then fluctuates seasonally as predators raise their young and limit prey populations.
A population of fish quickly increases in the spring when there is plenty of food but then decreases quickly in the fall when food is limited.
A population of wolves slowly increases because of limiting factors in the environment but then increases constantly when additional prey migrate into the environment.
Which sequence best orders ecological categories from the one with the fewest number of individuals to the one with the greatest number of individuals?
ecosystem, population, community, biome
population, community, ecosystem, biome
biome, population, community, ecosystem
community, biome, population, ecosystem
A researcher observing an ecosystem describes the amount of sunlight, precipitation, and type of soil present. Which factors is the researcher most likely describing?
biotic factors in a forest
biotic factors in a tundra
abiotic factors in a prairie
abiotic factors in an ocean
Energy pyramids describe food and energy relationships within an ecosystem. Which factor most likely limits the number of levels an energy pyramid can have?
biomass of the top-level organisms
predation by the top-level organisms
energy loss between each level of organisms
chemical energy being decomposed at each level of organisms
Orchids living in tropical rainforests often grow on the branches of trees to access sunlight. The trees are not affected by the orchids. Which term best classifies the relationship between the orchids and the trees?
predation
parasitism
competition
commensalism
Why are nonnative species often considered a disturbance in an ecosystem?
They increase mutations.
They compete for resources.
They have special growth needs.
They cause increased biodiversity.
Which set of ecological organization levels is most likely to contain the largest variety of species?
multiple biomes in a biosphere
multiple ecosystems in a biome
multiple individuals in a population
multiple populations in a community
Strep throat is a common human illness often caused by the bacterium Streptococcus pyogenes. Which term best classifies the colonies of Streptococcus pyogenes in a person with strep throat?
a population
an organelle
a community
an ecosystem
Ash from a volcanic eruption decreases the amount of available solar energy for a region. Which statement describes how a decrease in available sunlight will most likely affect ecosystems of this region?
Producer populations will decrease, causing a decrease in consumer populations.
Producer populations will decrease, causing an increase in consumer populations.
Decomposer populations will increase, causing a decrease in consumer populations.
Decomposer populations will increase, causing an increase in consumer populations.
A student studying the biosphere makes a list of biotic and abiotic characteristics of various biomes. Which characteristic is considered a biotic factor?
dry, sandy, nutrient-poor soil in a desert
less than 25 cm of precipitation in a desert
evergreen trees present in a coniferous forest
temperature range of -40 to 40°C in a grassland
Tadpoles grown in ponds with high densities of tadpoles have lower survival and growth rates than tadpoles grown in ponds with lower densities of tadpoles . Which interaction between tadpoles grown in high-tadpole-density ponds would most likely cause the decreased survival and growth rates?
symbiosis
mutualism
competition
commensalism
Which example describes a mutualistic relationship between organisms?
Young wasps prey on caterpillars.
Crabs eat the remains of dead fish.
Ants protect a tree on which they feed.
Tapeworms feed on food in the intestines of cats.
In the following food chain, which organisms are autotrophs?
algae → mosquitoes → salmon → bears
bears only
algae only
salmon and bears
algae and mosquitoes
Which statement best describes a contribution that decomposers make to an ecosystem?
They reduce the atomic mass of carbon atoms.
They increase the recycling of carbon-containing molecules.
They reduce the total number of carbon atoms in the atmosphere.
They increase the total number of carbon nuclei within the atoms.
