Ecology Unit Exam

Abigail, Liam, and Ethan are exploring the woods when they learn about deer ticks, tiny creatures that feed on the blood of warm-blooded animals like mice, deer, and even humans! These ticks can spread Lyme disease. What is the best way to describe a deer tick?

• predator

• parasite

• scavenger

• host

Henry, Hannah, and Abigail are exploring the food web shown above. Can you help them figure out which level—A, B, or C—has the least total available energy? Explain your answer so they can understand your reasoning!

Daniel, Abigail, and Priya are exploring the mysteries of an energy pyramid, just like the one shown below. If they want to discover which organisms would most likely be found at level A, what should they look for?

• birds

• mammals

• algae

• worms

Ethan, Abigail, and Noah are on a science adventure! They want to know: What is the portion of Earth in which all life exists called?

• the climax stage

• biosphere

• population

• biotic community

Noah, Maya, and Lily are exploring the ecosystem shown in the diagram below. They’re trying to figure out what keeps all the plants and animals energized! Can you help them out?

What is the primary source of energy in this environment?

• cellular respiration in the plants

• energy from minerals in the soil

• fossil fuels

• solar energy

Luna, Evelyn, and Jackson are exploring a pond for their science project. Which list contains only abiotic conditions they might observe in the pond ecosystem?

• temperature of the water, green plant populations, dissolved minerals in the water

• temperature of the water, dissolved oxygen in the water, dissolved minerals in the water

• bacteria, dissolved minerals in the water, temperature of the water

• dissolved oxygen in the water, fish populations,insect populations

Imagine Emma, Michael, and Sophia are watching squirrels in the park. Which scenario best shows direct competition within a species?

• A chipmunk is caught and eaten by a hungry fox

• A deer attempts to escape a mountain lion that is chasing it

• Two muskrats mate and produce a litter of offspring

• Several squirrels eat acorns from the oak tree where they live

Jackson, Nora, and Scarlett are exploring a vacant lot and spot rye grass, dandelions, grasshoppers, slugs, shrews, and ladybugs. What do all these organisms together represent?

• ecosystem

• population

• biome

• community

Zoe, Abigail, and Olivia are studying the graph below, which shows how the number of individuals in a population changes over time in a stable ecosystem. They start making predictions about what will happen next!

Which statement best describes the trend shown in this graph?

• Ecosystem conditions will eventually cause a population to become extinct

• In a stable ecosystem, the number of individuals in a population is usually maintained within a certain range

• The interactions between a population and various factors in an environment are always predictable

• In order for any ecosystem to maintain a balance, populations must be reduced to half their original number

Priya, Aria, and Olivia are learning about the emerald ash borer, a sneaky insect that is believed to have hitched a ride to the United States from China in shipping containers. This little bug attacks ash trees, eventually killing them and upsetting the balance of the ecosystem. The girls wonder: What does the presence of the emerald ash borer in the United States show about how humans have impacted the environment?

• purposely introduced an insect to correct a problem in an ecosystem

• used an insect to remove one insect species and replace it with another

• worked to increase the biodiversity in a particular area

• altered the equilibrium in an ecosystem by introducing a new species