Chapter 4 - Ecosystems

Every year, Xavier, with the help of his friends Emma and Mia, plants a vegetable garden in the same patch of soil. They notice that each year, the plants seem to grow less vigorously and yield fewer vegetables. Which of these processes could be the culprit behind Xavier, Emma, and Mia's gardening woes?

• the rate at which soil bacteria perform photosynthesis

• the rate at which soil bacteria perform denitrification

• the rate at which soil bacteria perform nitrogen fixation

• the rate at which soil bacteria perform chemosynthesis

Imagine you're an explorer like Isla or Grace, venturing into the world of autotrophs! Can you classify these amazing organisms into two groups based on which of these exciting properties?

• energy source, either sunlight or chemicals

• food type, either plant matter or animal matter

• food quality, either living matter or dead matter

• water quality, either fresh water or salt water

In the bustling community of Meadowville, rabbits like Oliver, Jackson, and Rohan munch on grasses, clover, roots, seeds, and even tree bark. Can you identify the fellow Meadowville residents who share the same dining habits as these rabbits?

• Snakes, hawks, and other animals that feast on rabbits

• Community members that have playful interactions with rabbits

• Meadow animals that are about the same size as a rabbit

• Meadow animals that enjoy a plant-based diet just like the rabbits

Luna and Avery are on an exciting ocean adventure to explore the mysteries of the food web! Which step would be most thrilling for them to take in order to discover the primary producers of the ocean's food web?

• Search for floating plants, like magical water lilies.

• Hunt for tiny phytoplankton that dance on the ocean surface.

• Chase after small animal plankton near the ocean surface.

• Dive deep to find plants or animals living along the ocean floor.

Imagine you're on a wild adventure with Daniel, Anika, and Scarlett, exploring a mysterious ecosystem! The diagram shows a model of feeding relationships. What do the arrows leading to and from the raccoon reveal about its role in this ecosystem?

• The raccoon is part of several food chains, but not a food web.

• The raccoon is part of several food chains and several food webs.

• The raccoon is part of one food web, but no food chains.

• The raccoon is part of one food web and several overlapping food chains.

Anika and Samuel are on a thrilling quest to discover an organism that performs the magical process of denitrification. Which adventurous path should they embark on to achieve success?

• Investigate phytoplankton that perform photosynthesis.

• Explore ocean-dwelling creatures that engage in chemosynthesis.

• Search for soil bacteria that transform atmospheric nitrogen into nitrates.

• Hunt for soil bacteria that convert nitrates into nitrogen gas.

Imagine you're on a thrilling adventure with Ethan, William, and Aria in the magical world of EcoLand! Which statement best describes the role of all primary producers in this enchanted ecosystem?

• All harness the energy of sunlight through the process of photosynthesis.

• All take in energy to assemble energy-rich compounds.

• All are small, single-celled organisms, such as bacteria and algae.

• All take in food and break it apart to release energy.

Luna is on a thrilling adventure to classify a group of organisms in the enchanted forest. These organisms are either magical primary producers or mystical consumers. Can you help Luna discover the direct source of energy for all of the mystical consumers?

• either magical producers or other mystical consumers

• magical producers only

• nonliving sources, such as sunlight

• other mystical consumers only

Imagine you're on a thrilling adventure with Zoe, Aria, and Isla in the jungle! Which of the following BEST describes the flow of energy through a food chain as you explore the wild ecosystem?

• Energy flows between primary producers and consumers, in either direction.

• Energy flows from consumers to primary producers, in one direction only.

• Energy flows from primary producers to consumers, in one direction only.

• Energy flows between primary producers and consumers, in an endless cycle.

Grace and Henry are exploring a magical ecosystem model. Can you help them figure out what the diagram represents?

• the total biomass in each trophic level

• the total amount of energy in the ecosystem

• the relative amount of energy available at each trophic level

• the conservation of energy as energy transfers between organisms