NUTRITION 3 - Respiratory System worksheet - Free Printable

Let's solve the worksheet step by step and explain each answer.

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1.1. Answer the questions using the words provided in the box:

Words: *oxygen, involuntary, carbon dioxide*

#### a) What gas does human beings take in when we breathe?
We inhale _________.
✔ Answer: *oxygen*
🔹 Explanation: When we breathe in (inhale), we take in oxygen from the air. Oxygen is essential for cellular respiration, where it helps produce energy in our cells.

#### b) What gas do human beings eliminate during respiration?
We exhale _________ _________.
✔ Answer: *carbon dioxide*
🔹 Explanation: During cellular respiration, our body produces carbon dioxide as a waste product. This gas is transported to the lungs and expelled when we exhale.

#### c) Is respiration a voluntary or involuntary movement?
It is an _________ movement.
✔ Answer: *involuntary*
🔹 Explanation: Breathing (respiration) is controlled by the brainstem and happens automatically without conscious effort. While we can control breathing temporarily (e.g., holding our breath), it is primarily an involuntary process.

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1.2. Name the organs of the respiratory system

We are given a diagram with numbered labels and a list of organs:

Organs to use:
- Nose
- Bronchioles
- Larynx
- Trachea or windpipe
- Bronchi
- Pharynx
- Lungs
- Alveolar sacs or alveoli

Now let’s match the numbers on the diagram:

#### 1) → Nose
🔹 The topmost part of the respiratory system; air enters through the nose.

#### 2) → Pharynx
🔹 Also known as the throat; connects the nasal cavity and mouth to the larynx.

#### 3) → Larynx
🔹 Commonly called the voice box; located below the pharynx and above the trachea.

#### 4) → Trachea or windpipe
🔹 A tube that carries air from the larynx to the bronchi.

#### 5) → Bronchi
🔹 The two main branches of the trachea that enter the lungs (right and left bronchus).

#### 6) → Bronchioles
🔹 Smaller branches of the bronchi that lead into the lungs' alveoli.

#### 7) → Alveolar sacs or alveoli
🔹 Tiny air sacs in the lungs where gas exchange occurs (oxygen enters blood, CO₂ exits).

#### a) → Lungs
🔹 The large organs where gas exchange takes place; shown as the pink structures on either side.

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✔ Final Answers:

#### 1.1:
a) We inhale oxygen.
b) We exhale carbon dioxide.
c) It is an involuntary movement.

#### 1.2:
1) Nose
2) Pharynx
3) Larynx
4) Trachea or windpipe
5) Bronchi
6) Bronchioles
7) Alveolar sacs or alveoli
a) Lungs

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This completes the worksheet! Let me know if you'd like a printable version or a labeled diagram explanation.