4.LS2.1 – Flow of Matter
4.LS2.2 – Interconnected Roles in a Food Web
4.LS2.3 – Effects of Introducing or Removing Species
4.LS2.4 – Environmental Change
4.ESS2.3 – Organisms Affecting Physical Characteristics of Regions
100
Which statement best describes the energy relationship between grass, rabbits, and the Sun?
A. Rabbits get energy from grass, and grass gets energy from sunlight.
B. Grass and rabbits both make food from sunlight.
C. Rabbits make food from sunlight, and grass does not.
D. Neither grass nor rabbits depend on the Sun.
A. Rabbits get energy from grass, and grass gets energy from sunlight.
Explanation: Grass is a producer—it makes food using sunlight. Rabbits are consumers that eat grass. The Sun provides the energy that starts the food chain.
100
A black bear eats nuts, berries, insects, fish, and honey. What type of consumer is it?
A. prey
B. decomposer
C. omnivore
D. herbivore
C. omnivore
Explanation: Bears eat both plants (nuts, berries, honey) and animals (fish, insects). That makes them omnivores.
100
A food web is shown in the diagram.
Which organisms do lizards eat?
a) cacti and rats
b) cacti and cayotes
c) shrubs and insects
d) shrubs and roadrunners
✅ Correct Answer: C. shrubs and insects
Explanation:
Lizards are consumers that feed on both plants (shrubs) and small animals (insects). They do not eat rats, coyotes, or roadrunners. Instead, coyotes and roadrunners are predators that may eat lizards.
👉 In short: Lizards eat shrubs and insects, not larger animals.
100
Coyotes, deer, and birds live in a meadow near a shopping mall. Humans pave over the meadow to create a parking lot. Many coyotes, deer, and birds move out of the area.
How have humans affected the area around the mall?
A. Humans increased available fresh water for the animals.
B. Humans caused an increase in the number of animals around the mall.
C. Humans took away land the animals need to live.
D. Humans gave the animals new locations to hide.
The correct answer is C. Humans took away land the animals need to live.
By paving the meadow for a parking lot, humans destroyed the animals’ habitat. This forced many animals to leave the area. The other answers do not describe what actually happened in the passage.
100
Which example shows a plant changing the physical characteristics of a region?
A. Vines grow strong-smelling flowers.
B. Trees provide food for bugs.
C. Rabbits eat grass in a field.
D. Roots break apart rocks.
The correct answer is D.
Roots break apart rocks.
Plants can physically change their environment. Roots grow into cracks in rocks and break them apart over time, which changes the land. The other options are about providing food or appearance, not physical characteristics.
200
Which type of organism is most important in returning nutrients to the soil?
A.decomposer
B.omnivore
C. producer
D. carnivore
A.decomposer
Explanation: Decomposers like fungi and bacteria break down dead organisms and waste, putting nutrients back into the soil for plants to use.
200
In a forest food web, if the snake population suddenly drops, which group would most likely grow in number?
A. berries
B. eagles
C. mushrooms
D. mice
D. Mice
Explanation: Snakes eat mice. If snakes decrease, fewer mice are eaten, so the mouse population will increase.
200
The diagram shows a grassland food chain:
A population of insect-eating birds migrates into the grassland. Which population would most likely be negatively affected first as a result?
A. Grasses
B. Frogs
C. Hawks
D. Snakes
The correct answer is B. Frogs.
The insect-eating birds will compete with frogs for food (grasshoppers).
With fewer grasshoppers available, frogs will struggle to find enough to eat.
This will negatively affect the frog population first.
👉 The other groups (snakes and hawks) may be affected later, but only after frogs decline. Grasses won’t be hurt because birds and frogs don’t eat plants.
200
Which event would most likely cause deer to leave or die in a woodland?
A. snowstorm
B. sinkhole
C. forest fire
D. rainstorm
C. forest fire
Explanation: Fires destroy food and shelter. Deer can survive normal storms, but fire forces them to leave or kills them.
200
A beaver builds a dam across a narrow part of a river to use as a lodge to raise its young.
How will the beaver’s dam impact the area?
Responses
- A) The beaver will clear-cut thousands of trees to build the dam.
- B) The location of the beaver’s dam will cause floods upstream.
- C) The beaver will only hunt freshwater fish in the river surrounding its dam.
- D) The pollution in the river will increase due to the beaver’s dam.
A. The beaver will clear-cut thousands of trees to build the dam.
❌ Not true — beavers use some trees, but not thousands.
B. The location of the beaver’s dam will cause floods upstream.
✅ Correct — when beavers block a river, the water builds up behind the dam, creating ponds and flooding upstream areas. This changes the physical characteristics of the land.
C. The beaver will only hunt freshwater fish in the river surrounding its dam.
❌ Beavers don’t eat fish; they eat bark, leaves, and plants.
D. The pollution in the river will increase due to the beaver’s dam.
❌ Beavers don’t cause pollution.
300
Examine the food web. Which group shows consumers?
A. flower, lizard, and grass
B. lizard, beetle, and bird
C. beetle, flower, and grass
D. bird, flower, and beetle
B. lizard, beetle, and bird
Explanation: Consumers are animals that eat other organisms. Flowers and grass are producers, but lizards, beetles, and birds eat plants or animals.
300
The food web shows an ecosystem. Which change will likely cause the dragonfly population to decrease?
A. removing butterflies
B. adding more roses
C. adding more fruit flies
D. removing all thrushes
A. removing butterflies
Explanation: Butterflies are part of the dragonfly’s food source. If they disappear, dragonflies will have less to eat, lowering their population.
300
A deer population suddenly increases. What is the most likely cause?
A. Food sources scarce (hard to find)
B. Their habitat was destroyed
C. Their predators were disappearing
D. A disease spreading
C. Their predators were disappearing
Explanation: If predators like wolves or mountain lions are gone, deer don’t get eaten as often, so their population grows.
300
Which change would most harm a squirrel’s habitat?
A. planting pine seedlings
B. seasonal weather changes
C. new plant growth
D. cutting down trees for houses
D. cutting down trees for houses
Explanation: Squirrels rely on trees for food (nuts) and shelter. Removing trees directly harms their habitat.
300
In tropical rainforests, buttress trees grow and have large aboveground root systems. The image shows a buttress tree and its root system.
Which claim best supports that organisms affect the physical characteristics of a tropical rain forest?
- A) Roots provide support for the tree in an area with nutrient-poor soils.
B) Roots provide food for insects since they are above the soil.
C) Roots create areas for animals to lay eggs to protect their young.
D) Roots create dams that decrease flooding in the forest.
- A) Roots provide support for the tree in an area with nutrient-poor soils.
Why: Roots change the physical environment by holding soil in place and helping trees stand in poor soil. The other choices are about food or habitat, not physical characteristics.
400
eating deer
eating nuts and seeds
eating fruits
absorbing sunlight
breaking down animal waste
Which two methods would a small songbird most likely use to get energy?
A. breaking down animal waste
B. eating deer
C. eating nuts and seeds
D. eating fruits
C. eating nuts and seeds
D. eating fruits
Explanation: Songbirds are consumers. They don’t eat deer or waste, and they can’t make energy directly from sunlight like plants. They rely on seeds and fruits for food.
400
The image shows a food web. Which organisms are eaten by the top consumers?
A. squirrels and rabbits
B. rabbits and grasshoppers
C. foxes and eagles
D. eagles and squirrels
A. squirrels and rabbits
Explanation: Top consumers (like eagles and foxes) eat smaller animals. They don’t eat other top predators; they usually eat prey like rabbits and squirrels.
400
The number of fish in a lake suddenly increases. How will the increase most likely affect the lake?
A. There will be less water in the lake.
B. More plants will grow in the lake.
C. More frogs will live in the lake.
D. There will be fewer insects in the lake.
✅ Correct Answer: D. There will be fewer insects in the lake.
Explanation:
When the number of fish increases in a lake, the balance of the food web changes. Most fish eat insects or insect larvae that live in the water. If there are more fish, they will eat more insects, which means the insect population will decrease.
400
If a tall tree falls in a crowded forest, which resource becomes more available to nearby plants?
A. water
B. sunlight
C. soil
D. air
B. sunlight
Explanation: When a tree falls, it opens space for sunlight to reach plants that were shaded. This helps them grow.
400
Which three actions would change the area where animals live?
A. dolphins swimming in groups
B. herd of cattle eating all the grass in a field
C. octopuses piling pebbles
D. monkeys resting in tree shade
E. beavers building a dam
B. herd of cattle eating all the grass in a field
C. octopuses piling pebbles
E. beavers building a dam
Explanation: These actions physically change the environment:
Cattle eat all the grass, changing the land.
Octopuses pile pebbles, changing the sea floor.
Beavers build dams, changing rivers.
Monkeys sitting and dolphins swimming don’t change their environment.