I knew that!
What is the main source of energy for almost all food webs on Earth?
A. Soil
B. The Sun
C. Water
D. Wind
B. The Sun
When a top predator is removed from a food web, one likely result is:
A. All populations stay the same
B. Prey populations increase
C. Producers die immediately
D. Decomposers become producers
B. Prey populations increase
Which of the following is a biotic factor?
A. Temperature
B. Soil
C. Water
D. A mushroom
D. A mushroom
An omnivore is an animal that:
A. Eats only plants
B. Eats only animals
C. Eats both plants and animals
D. Makes its own food
C. Eats both plants and animals
Which organisms make their own food using sunlight?
A. Consumers
B. Decomposers
C. Producers (plants)
D. Predators
C. Producers (plants)
Which change is an example of an abiotic change affecting a habitat?
A. New predators moving in
B. Decrease in rainfall causing drought
C. Increase in plant-eating insects
D. More fungi appearing
B. Decrease in rainfall causing drought
An animal that eats only plants is called a:
A. Carnivore
B. Omnivore
C. Herbivore
D. Decomposer
C. Herbivore
Which organisms are usually found at the base (lowest level) of most food webs?
A. Top predators
B. Producers (plants)
C. Decomposers
D. Omnivores
Producers (plants)
If many producers (plants) in an ecosystem die, what is the most likely effect on consumers?
A. Consumers will have more energy.
B. Consumer populations will decrease.
C. Consumers will become producers.
D. There will be no change.
B. Consumer populations will decrease.
Which is an abiotic factor?
A. Bacteria
B. Plants
C. Sunlight
D. Animals
D. Animals
Which statement best describes how energy moves through an ecosystem?
A. Energy cycles in a circle and returns to producers unchanged.
B. Energy flows one way from producers to consumers and is lost as heat.
C. Energy disappears at each step and is created later.
D. Energy moves only between decomposers
B. Energy flows one way from producers to consumers and is lost as heat.
Which diagram shows a single path of energy from one organism to another (for example: grass → rabbit → fox)?
A. Food web
B. Pyramid chart
C. Food chain
D. Energy map
C. Food chain
A diagram that shows many interconnected food chains in an ecosystem is called a:
A. Food chain
B. Food web
C. Water cycle
D. Energy ladder
B. Food web
What role do bacteria and fungi often play in ecosystems?
A. Primary consumers
B. Producers of sunlight
C. Decomposers that recycle nutrients
D. Top predators
C. Decomposers that recycle nutrients
Which action would most directly slow nutrient recycling in soil?
A. Planting more trees
B. Polluting the soil and killing decomposers
C. Increasing sunlight
D. Adding more water
B. Polluting the soil and killing decomposers
What do decomposers do in an ecosystem?
A. Make food from sunlight
B. Break down dead organisms and return nutrients to the soil
C. Eat only plants
D. Increase the amount of sunlight
B. Break down dead organisms and return nutrients to the soil