Science: Bones and muscles | Worksheet | PrimaryLeap.co.uk - Free Printable

To solve the problem, we need to fill in the missing spaces with the appropriate words from the list provided. Let's go through each sentence step by step and determine the correct word for each blank.

List of Words:

- ribs
- skeletons
- move
- joints
- pairs
- skull
- bones
- easily
- protection
- expanding

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Sentence 1:

"Our skeletons are very useful. They have three functions, ________, support and ________."

- Functions of the skeleton: The skeleton has three main functions: protection, support, and movement.
- From the list, the words that fit are protection and movement.

So, the sentence becomes:
"Our skeletons are very useful. They have three functions, protection, support and movement."

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Sentence 2:

"The ________ protects our brains, the ________ protect our heart and lungs."

- Protection of organs:
- The skull protects the brain.
- The ribs protect the heart and lungs.

So, the sentence becomes:
"The skull protects our brains, the ribs protect our heart and lungs."

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Sentence 3:

"Without our ________ our bodies would collapse."

- Support structure: Without bones, our bodies would collapse because bones provide structural support.

So, the sentence becomes:
"Without our bones our bodies would collapse."

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Sentence 4:

"Our bones are connected by ________. Our knees are joints."

- Connections between bones: Bones are connected by joints.

So, the sentence becomes:
"Our bones are connected by joints. Our knees are joints."

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Sentence 5:

"Muscles are attached to the ________ of our skeleton. Muscles allow our bones to ________ by contracting and ________."

- Muscle attachment: Muscles are attached to the bones of the skeleton.
- Muscle function: Muscles allow bones to move by contracting and expanding.

So, the sentence becomes:
"Muscles are attached to the bones of our skeleton. Muscles allow our bones to move by contracting and expanding."

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Sentence 6:

"Muscles usually work in ________."

- Muscle pairing: Muscles usually work in pairs (e.g., biceps and triceps).

So, the sentence becomes:
"Muscles usually work in pairs."

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Sentence 7:

"Cartilage protects the bones and allows them to move ________."

- Cartilage function: Cartilage protects the bones and allows them to move easily.

So, the sentence becomes:
"Cartilage protects the bones and allows them to move easily."

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Final Answer:

Here is the completed worksheet:

```
Our skeletons are very useful. They have three functions, protection, support and movement. The skull protects our brains, the ribs protect our heart and lungs. Without our bones our bodies would collapse. Our bones are connected by joints. Our knees are joints. Muscles are attached to the bones of our skeleton. Muscles allow our bones to move by contracting and expanding. Muscles usually work in pairs. Cartilage protects the bones and allows them to move easily.
```

Boxed Final Answer:

\boxed{
\text{protection, movement, skull, ribs, bones, joints, bones, move, expanding, pairs, easily}
}