Food Chain Worksheets - Free Printables - Free Printable

Food Chain Worksheet Solution

#### Section 1: Fill in the blank spaces

1. A food chain starts with a _______ and ends with a _______. Green plants are called _______ because they use the light energy of the sun to produce food using carbon dioxide and water through a process called _______. Animals cannot make their food and thus are called _______.

- Answer:
A food chain starts with a producer and ends with a decomposer. Green plants are called producers because they use the light energy of the sun to produce food using carbon dioxide and water through a process called photosynthesis. Animals cannot make their food and thus are called consumers.

2. There are ___ main trophic levels in a food chain. They are ______, ______, ______, and ______. Apart from the said trophic levels, ______ have no natural predators except humans. Then, ______, like fungi and bacteria, turn dead ______ into inorganic materials in the soil.

- Answer:
There are 4 main trophic levels in a food chain. They are producers, primary consumers, secondary consumers, and tertiary consumers. Apart from the said trophic levels, humans have no natural predators except other humans. Then, decomposers, like fungi and bacteria, turn dead organisms into inorganic materials in the soil.

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#### Section 2: Use the food web diagram below to answer the following questions.

The food web diagram shows various organisms and their feeding relationships. Here is the diagram for reference:

- Producers: Grass, Shrub, Tree
- Primary Consumers: Shrew, Squirrel, Grasshopper, Rabbit, Deer
- Secondary Consumers: Snake, Bird
- Tertiary Consumers: Hawk, Mountain Lion

1. Write any two longest food chains in the food web.

To identify the longest food chains, we need to trace the path from a producer (starting point) to a top predator (ending point), including as many trophic levels as possible.

- Longest Food Chain 1:
Grass → Grasshopper → Bird → Mountain Lion
- Explanation:
- Grass (producer) is eaten by Grasshopper (primary consumer).
- Grasshopper is eaten by Bird (secondary consumer).
- Bird is eaten by Mountain Lion (tertiary consumer).

- Longest Food Chain 2:
Tree → Deer → Mountain Lion
- Explanation:
- Tree (producer) is eaten by Deer (primary consumer).
- Deer is eaten by Mountain Lion (tertiary consumer).

- Alternative Longest Food Chain:
Shrub → Rabbit → Snake → Hawk
- Explanation:
- Shrub (producer) is eaten by Rabbit (primary consumer).
- Rabbit is eaten by Snake (secondary consumer).
- Snake is eaten by Hawk (tertiary consumer).

Final Answer for Question 1:
\[
\boxed{\text{Grass → Grasshopper → Bird → Mountain Lion, Tree → Deer → Mountain Lion}}
\]

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Summary of Solutions:

1. Section 1 Answers:
- A food chain starts with a producer and ends with a decomposer.
- Green plants are called producers because they use sunlight to produce food through photosynthesis.
- Animals are called consumers.
- There are 4 main trophic levels: producers, primary consumers, secondary consumers, and tertiary consumers.
- Humans have no natural predators except other humans.
- Decomposers like fungi and bacteria turn dead organisms into inorganic materials.

2. Section 2 Answers:
- Two longest food chains:
1. Grass → Grasshopper → Bird → Mountain Lion
2. Tree → Deer → Mountain Lion

\[
\boxed{\text{Grass → Grasshopper → Bird → Mountain Lion, Tree → Deer → Mountain Lion}}
\]