Food chains worksheet for Grade 3 science, teaching how energy moves through living things with fill-in-the-blank exercises.

Task Overview:

The task involves completing food chains by filling in the missing organisms. A food chain shows how energy moves from the sun through living things. The provided example is:
Sun → grass → rabbit → fox.

Key Concepts:

1. Producers: Organisms that produce their own food using sunlight (e.g., plants, algae).
2. Consumers: Organisms that eat producers or other consumers.
- Primary Consumers: Eat producers (herbivores).
- Secondary Consumers: Eat primary consumers (carnivores or omnivores).
- Tertiary Consumers: Eat secondary consumers (top predators).

Solution:

#### Food Chain 1:
Sun → _______ → butterfly → bird → snake

- Step 1: Identify what butterflies eat. Butterflies typically feed on flowers or plants.
- Step 2: Fill in the missing organism: flower.

Completed Chain:
Sun → flower → butterfly → bird → snake

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#### Food Chain 2:
Sun → algae → krill → _______ → orca

- Step 1: Identify what eats krill. Krill are small shrimp-like creatures that are prey for many marine animals, such as whales, seals, and fish.
- Step 2: Since the next organism in the chain is an orca (a large marine predator), the missing link must be a smaller marine animal that orcas eat. A common choice is seaweed, which krill consume, but since seaweed is not listed, we can infer it might be a fish or another small marine creature. However, based on the options provided, seaweed is the closest match as a producer in this context.
- Step 3: Fill in the missing organism: seaweed.

Completed Chain:
Sun → algae → krill → seaweed → orca

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#### Food Chain 3:
Sun → wheat → mouse → _______

- Step 1: Identify what eats mice. Mice are prey for various predators, including birds, snakes, and owls.
- Step 2: From the given options, the most suitable predator of mice is the owl.
- Step 3: Fill in the missing organism: owl.

Completed Chain:
Sun → wheat → mouse → owl

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#### Food Chain 4:
_______ → acorn → squirrel → coyote

- Step 1: Identify what produces acorns. Acorns are produced by trees, specifically oak trees.
- Step 2: Since the sun provides energy to producers, the missing link must be the sun.
- Step 3: Fill in the missing organism: sun.

Completed Chain:
Sun → acorn → squirrel → coyote

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#### Food Chain 5:
Sun → _______ → fish → seal → shark

- Step 1: Identify what fish eat. Fish typically consume smaller aquatic organisms, such as plankton, algae, or smaller fish. However, since the options provided do not include plankton or algae, the closest match is seaweed, which is a type of aquatic plant.
- Step 2: Fill in the missing organism: seaweed.

Completed Chain:
Sun → seaweed → fish → seal → shark

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Final Answer:

1. Sun → flower → butterfly → bird → snake
2. Sun → algae → krill → seaweed → orca
3. Sun → wheat → mouse → owl
4. Sun → acorn → squirrel → coyote
5. Sun → seaweed → fish → seal → shark

Boxed Final Answer:
\boxed{
\begin{aligned}
1. & \text{ Sun → flower → butterfly → bird → snake} \\
2. & \text{ Sun → algae → krill → seaweed → orca} \\
3. & \text{ Sun → wheat → mouse → owl} \\
4. & \text{ Sun → acorn → squirrel → coyote} \\
5. & \text{ Sun → seaweed → fish → seal → shark}
\end{aligned}
}