Food Chains Food Web and Energy Pyramid Worksheet.doc - Food ... - Free Printable

Let’s go step by step through the worksheet.

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Part 1: Food Chain with Grass, Rabbit, Fox

We are given a food chain:
Grass → Rabbit → Fox

This means:
- Rabbit eats grass (so rabbit is primary consumer)
- Fox eats rabbit (so fox is secondary consumer)

Now answer the questions:

a. What type of organism is the green plant?
Green plants make their own food using sunlight — they’re called producers.

✔ Answer: Producer

b. Which animal is the herbivore?
Herbivores eat only plants. The rabbit eats grass → so rabbit is the herbivore.

✔ Answer: Rabbit

c. If more rabbits came into this habitat, what would happen to the amount of grass? Why?
More rabbits = more animals eating grass → grass will decrease because it’s being eaten faster than it can grow back.

✔ Answer: The amount of grass would decrease because more rabbits are eating it.

d. How many levels are in this food chain?
Count the steps:
Level 1: Grass (producer)
Level 2: Rabbit (primary consumer)
Level 3: Fox (secondary consumer)

That’s 3 levels.

✔ Answer: 3

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Part 2: Owl eats snake, snake eats squirrel, squirrel eats nut

Food chain: Nut → Squirrel → Snake → Owl

Note: “Nut” comes from an oak tree — but since the question says “squirrel ate a nut”, and we’re building the chain based on who eats whom, we start with the nut as the producer-level item (even though technically the tree makes the nut). But for simplicity in this context, we treat “nut” as the base energy source.

But wait — the instruction says: *“Organism Food Source owl snake squirrel Oak Tree”* — that seems like a hint to build the chain starting from Oak Tree.

Actually, let’s re-read:
> An owl eats a snake, the snake eats a squirrel, the squirrel ate a nut. Organism Food Source owl snake squirrel Oak Tree

It looks like they want us to write the full chain including the oak tree, since nuts come from oak trees.

So correct chain should be:
Oak Tree → Nut → Squirrel → Snake → Owl?
Wait — no. Actually, squirrels eat nuts directly — so maybe:

Oak Tree produces nuts → Squirrel eats nut → Snake eats squirrel → Owl eats snake

But in food chains, we usually list organisms, not parts (like “nut”). So better to say:

Oak Tree → Squirrel → Snake → Owl

Because the squirrel gets its energy from the oak tree (via the nut), so oak tree is the producer.

The problem says: “Organism Food Source owl snake squirrel Oak Tree” — which might mean fill in the blanks:

Owl eats → snake
Snake eats → squirrel
Squirrel eats → ? (should be oak tree or nut?)
And then “Oak Tree” is listed at the end — probably meaning it’s the producer.

Looking at the blank line:
“An owl eats a snake, the snake eats a squirrel, the squirrel ate a nut. Organism Food Source owl snake squirrel Oak Tree”

Then below:
“snake squirrel Oak Tree NUTSquirrel Nuts” — this seems messy. Probably a typo.

I think the intended chain is:

Producer: Oak Tree
Primary Consumer: Squirrel (eats acorns/nuts from oak tree)
Secondary Consumer: Snake (eats squirrel)
Tertiary Consumer: Owl (eats snake)

So food chain: Oak Tree → Squirrel → Snake → Owl

Now answer the questions:

a. Using the food chain you created, identify the trophic level for each organism:

- Oak Tree → Producer (trophic level 1)
- Squirrel → Primary Consumer (level 2)
- Snake → Secondary Consumer (level 3)
- Owl → Tertiary Consumer (level 4)

But the question says: “identify the trophic level for each organism” and gives blanks under:

Oak Tree ___
Squirrel ___
Snake ___
Owl ___

So:

Oak Tree → Producer
Squirrel → Primary Consumer
Snake → Secondary Consumer
Owl → Tertiary Consumer

Alternatively, if they want numbers:

Level 1: Oak Tree
Level 2: Squirrel
Level 3: Snake
Level 4: Owl

But since the first part used terms like “herbivore”, likely they want functional roles.

Wait — looking again at the worksheet layout:

After “Oak Tree Squirrel Snake Owl” there are lines underneath each word — probably to write their role.

Also, later it asks:

b. Which animal has the most amount of available energy?
In any food chain, producers have the most energy. Energy decreases as you go up levels.

So Oak Tree (producer) has the most energy.

But the question says “which animal” — oh! It says “animal”. Oak tree is not an animal.

Hmm. Let’s read carefully:

> b. Which animal has the most amount of available energy? _______

Animals in the chain: Squirrel, Snake, Owl

Among these, the one closest to the producer has the most energy → Squirrel (primary consumer)

Because energy flows: Oak Tree → Squirrel → Snake → Owl

Each step loses about 90% energy, so squirrel has more than snake, which has more than owl.

✔ So answer: Squirrel

> c. Which animal has the least amount of available energy? _______

Top predator → Owl

✔ Answer: Owl

Back to part a: “Using the food chain you created, identify the trophic level for each organism”

Given the words: Oak Tree, Squirrel, Snake, Owl

And blanks under them — likely to write:

Oak Tree: Producer
Squirrel: Primary Consumer
Snake: Secondary Consumer
Owl: Tertiary Consumer

Or if they want numerical levels:

Oak Tree: Level 1
Squirrel: Level 2
Snake: Level 3
Owl: Level 4

But since the first part didn’t use numbers, probably functional names.

However, looking at the very bottom, it says:

“b. Which animal has the most amount of available energy? _______”
“c. Which animal has the least amount of available energy? _______”

So for part a, it’s asking for trophic levels of all four, including oak tree.

I think safest is to use:

Oak Tree → Producer
Squirrel → Primary Consumer
Snake → Secondary Consumer
Owl → Tertiary Consumer

But let me check standard curriculum — often in middle school, they accept:

Producer, Primary Consumer, etc.

Alternatively, sometimes they say:

Autotroph, Heterotroph, etc. — but unlikely here.

Another way: perhaps they want the position number.

Wait — in the first food chain (grass-rabbit-fox), they asked “how many levels” — answered 3.

Here, if we include oak tree, it’s 4 levels.

But the question doesn’t ask for number of levels — it asks to identify trophic level for each organism.

I think writing the role is fine.

But to match format, let’s see how the first part was done.

In first part, they didn’t assign levels per organism — just asked total levels.

Here, it specifically says “identify the trophic level for each organism”

Perhaps they expect:

Oak Tree: 1st trophic level
Squirrel: 2nd trophic level
Snake: 3rd trophic level
Owl: 4th trophic level

That might be it.

Since energy decreases up the chain, and producers are level 1.

Yes, I think numerical levels are expected here.

Confirming with biology standards: Trophic levels are numbered starting from 1 for producers.

So:

Oak Tree → Trophic Level 1
Squirrel → Trophic Level 2
Snake → Trophic Level 3
Owl → Trophic Level 4

Perfect.

Now for b and c:

b. Which animal has the most amount of available energy?
Animals: Squirrel (level 2), Snake (level 3), Owl (level 4)
Most energy → lowest level among animals → Squirrel

c. Least energy → highest level → Owl

Final Answers:

For Part 1:

a. Producer
b. Rabbit
c. The amount of grass would decrease because more rabbits are eating it.
d. 3

For Part 2:

a.
Oak Tree: Trophic Level 1
Squirrel: Trophic Level 2
Snake: Trophic Level 3
Owl: Trophic Level 4

b. Squirrel
c. Owl

But wait — in part 2a, the worksheet shows:

“Oak Tree Squirrel Snake Owl” with lines under each — so probably write the level under each.

Also, note that in the text it says “Organism Food Source owl snake squirrel Oak Tree” — which might be confusing, but I think it's just listing the organisms involved.

Another thing: in the chain, is "nut" considered? But nut is not an organism — it's a part of the oak tree. So we don't include it as a separate trophic level. The squirrel consumes the nut, which comes from the oak tree, so oak tree is still the producer.

Yes.

So final answers compiled.

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Final Answer:
Part 1:
a. Producer
b. Rabbit
c. The amount of grass would decrease because more rabbits are eating it.
d. 3

Part 2:
a. Oak Tree: Trophic Level 1, Squirrel: Trophic Level 2, Snake: Trophic Level 3, Owl: Trophic Level 4
b. Squirrel
c. Owl