Respiratory system online activity for Grade 8 - Free Printable

Let's solve the worksheet step by step.

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1. Label the parts of the respiratory system

We are given a diagram with numbered parts. Let’s identify each labeled part based on its position in the human respiratory system:

1. Nose – The air enters through the nose.
2. Nasal cavity / Nasal passage – Inside the nose, where air is filtered and warmed.
3. Larynx (voice box) – Located below the throat; connects the pharynx to the trachea.
4. Trachea (windpipe) – The tube that carries air from the larynx to the bronchi.
5. Bronchi – Two main branches from the trachea into the lungs.
6. Bronchioles – Smaller branches of the bronchi within the lungs.
7. Alveoli – Tiny air sacs in the lungs where gas exchange occurs.
8. Diaphragm – The muscle beneath the lungs that helps in breathing.

✔ So, labeling the blanks:
- 1: Nose
- 2: Nasal cavity
- 3: Larynx
- 4: Trachea
- 5: Bronchi
- 6: Bronchioles
- 7: Alveoli
- 8: Diaphragm

> Note: Some diagrams might label "pharynx" instead of nasal cavity for #2. But since #1 is clearly the nose, #2 is likely the nasal cavity, which is inside the nose.

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2. Complete the text about the process of respiration

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

Now fill in the blanks:

> 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 filled-in version:

> 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 – Labels:
1. Nose
2. Nasal cavity
3. Larynx
4. Trachea
5. Bronchi
6. Bronchioles
7. Alveoli
8. Diaphragm

#### Part 2 – Completion:
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 explains the human respiratory system and how respiration works!