Respiratory system online activity for Grade 8 - Free Printable

Let's solve the worksheet step by step.

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1. Write the parts of the respiratory system

We need to label the numbered parts in the diagram of the human respiratory system.

Here is the correct labeling based on standard anatomy:

- 1 → Nose
- 2 → Nasal cavity
- 3 → Larynx (voice box)
- 4 → Trachea (windpipe)
- 5 → Right lung
- 6 → Bronchi (plural of bronchus)
- 7 → Alveoli (tiny air sacs in the lungs where gas exchange occurs)
- 8 → Diaphragm (muscle below the lungs that helps with breathing)

✔ So, fill in the blanks as follows:

- 1: Nose
- 2: Nasal cavity
- 3: Larynx
- 4: Trachea
- 5: Right lung
- 6: Bronchi
- 7: Alveoli
- 8: Diaphragm

> Note: The image shows both lungs, but only one is labeled (5). "Right lung" is appropriate for 5; 6 points to the bronchi branching into the lungs.

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2. Complete the text about the process of respiration

Use the words provided:
- Breathe out
- Breathe in
- Blood
- Trachea
- Air
- Nose
- Bronchi
- Carbon dioxide
- Lungs
- Oxygen
- Nostrils

Now complete the sentences:

> First, air enters through our nostrils and nose
> The air goes down through the trachea and the bronchi
> The air enters in the lungs
> Oxygen (O₂) passes into the blood
> Carbon dioxide (CO₂) leaves our body when we breathe out

✔ Final completed paragraph:

> First, air enters through our nostrils and nose
> The air goes down through the trachea and the bronchi
> The air enters in the lungs
> Oxygen (O₂) passes into the blood
> Carbon dioxide (CO₂) leaves our body when we breathe out

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✔ Summary of Answers:

#### Part 1 – Labeling:
1. Nose
2. Nasal cavity
3. Larynx
4. Trachea
5. Right lung
6. Bronchi
7. Alveoli
8. Diaphragm

#### Part 2 – Fill-in-the-blank:
First, air enters through our nostrils and nose
The air goes down through the trachea and the bronchi
The air enters in the lungs
Oxygen (O₂) passes into the blood
Carbon dioxide (CO₂) leaves our body when we breathe out

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This completes the worksheet accurately and clearly!