Invertebrates online exercise - Free Printable

Let's solve this worksheet step by step, using the provided word banks and biological knowledge about insects, crustaceans, and arachnids.

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Section 1: Bees

Given words:
- wings
- exoskeleton
- eyes
- legs
- antennae
- insects
- abdomen
- herbivores

Statements:

1. Bees are ________. They have a thorax with six ________ and two ________, an ________, and a head with ________ and ________.

- Bees are insects.
- Insects have six legs (three pairs) and two wings (most bees have two wings).
- The body has three parts: head, thorax, and abdomen.
- Head has antennae and eyes.

✔ So:
> Bees are insects. They have a thorax with six legs and two wings, an abdomen, and a head with antennae and eyes.

2. Bees are ________. They eat nectar from flowers.

- Since they eat plant material (nectar), they are herbivores.

✔ herbivores

3. Bees have a thin ________ for protection.

- All arthropods have an exoskeleton.

✔ exoskeleton

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Section 2: Crabs

Given words:
- pincers
- exoskeleton
- Crustaceans
- legs

Statements:

1. Crabs are ________. They have eight ________ and two ________.

- Crabs are Crustaceans (a class of arthropods including crabs, lobsters, shrimp).
- Crabs have eight legs (four pairs) and two pincers (chelipeds).

✔ So:
> Crabs are Crustaceans. They have eight legs and two pincers.

2. Crabs have a thick ________.

- Like other arthropods, crabs have an exoskeleton, which is usually hard and thick in crustaceans.

✔ exoskeleton

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Section 3: Butterflies

Given words:
- legs
- exoskeleton
- eyes
- abdomen
- insects

Statements:

1. Butterflies are ________. They have a thorax with six ________ and wings, an ________, and a head with two ________.

- Butterflies are insects.
- They have six legs, wings, abdomen, and antennae on the head.
- But "antennae" isn't in the box — wait! Let's check the available words:
- legs, exoskeleton, eyes, abdomen, insects

Hmm — antennae is missing from the word bank here. But we have eyes.

Wait — let’s look at the sentence:
> "...and a head with two ________."

We need to pick from: legs, exoskeleton, eyes, abdomen, insects

Only eyes makes sense. But butterflies also have antennae — but since it's not in the box, maybe the intended answer is eyes?

However, looking back — the first section had antennae in its word bank, but this one doesn’t. That might be a mistake, but we must use only the given words.

So, the head has two eyes — that’s acceptable.

Also, they have six legs, wings, abdomen.

✔ So:
> Butterflies are insects. They have a thorax with six legs and wings, an abdomen, and a head with two eyes.

2. They have a thin ________ for protection.

- Again, all insects have an exoskeleton.

✔ exoskeleton

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Final Section: Word Bank at Bottom

This appears to be a list of possible words used throughout — likely just a reference or for another exercise. But we’ve already used:

- head
- exoskeleton
- abdomen
- legs
- mouth
- arachnids
- thorax
- carnivores

We didn’t use mouth, arachnids, thorax, or carnivores — but those aren’t needed for the sentences above.

Wait — did we miss anything?

Let’s double-check.

In the crab section, we used:
- Crustaceans
- legs
- pincers
- exoskeleton

In bee and butterfly, we used:
- insects
- legs
- wings
- abdomen
- eyes
- antennae (but not in butterfly section — that’s a problem)

Ah — in the butterfly section, the word bank does not include antennae, so we can’t use it.

But the sentence says: “a head with two ________”

We have to choose from: legs, exoskeleton, eyes, abdomen, insects

Only eyes fits — so we go with eyes.

But biologically, butterflies have antennae, not just eyes. But since it’s not in the box, we must assume the question expects eyes.

Alternatively, perhaps there's a typo in the word bank?

But based on what’s given, we proceed.

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✔ Final Answers:

#### Bees:
- Bees are insects. They have a thorax with six legs and two wings, an abdomen, and a head with antennae and eyes.
- Bees are herbivores. They eat nectar from flowers.
- Bees have a thin exoskeleton for protection.

#### Crabs:
- Crabs are Crustaceans. They have eight legs and two pincers.
- Crabs have a thick exoskeleton.

#### Butterflies:
- Butterflies are insects. They have a thorax with six legs and wings, an abdomen, and a head with two eyes.
- They have a thin exoskeleton for protection.

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🔍 Explanation:

- Insects (bees, butterflies): Have 3 body parts (head, thorax, abdomen), 6 legs, usually wings, antennae, and an exoskeleton. Most are herbivores (like bees and butterflies feeding on nectar).
- Crustaceans (crabs): Have 5 body segments, typically 10 legs (including pincers), no wings, and a thick exoskeleton.
- Exoskeleton: Hard outer shell made of chitin that protects and supports the body.
- Herbivores: Animals that eat plants (nectar = plant product).
- Antennae: Sensory organs on the head — important for smell and touch; present in insects but not listed in the butterfly word bank.

> Note: The absence of "antennae" in the butterfly word bank is likely an error. If this were a real test, you’d use eyes as the best fit among the options.

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✔ Final Filled Worksheet:

```
• Bees are insects. They have a thorax with six legs and two wings, an abdomen, and a head with antennae and eyes.
• Bees are herbivores. They eat nectar from flowers.
• Bees have a thin exoskeleton for protection.

• Crabs are Crustaceans. They have eight legs and two pincers.
• Crabs have a thick exoskeleton.

• Butterflies are insects. They have a thorax with six legs and wings, an abdomen, and a head with two eyes.
• They have a thin exoskeleton for protection.
```

✔ All blanks filled correctly using the provided words.