Blood vessels activity - Free Printable

Let's solve this step by step. The image is a worksheet about blood vessels, with a diagram and 11 questions. We'll go through the diagram labeling first, then answer each question.

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🔹 Diagram Labeling (Drag and Drop)

The diagram shows:

- A red vessel on the left → carries blood from the heart → this is an artery
- A blue vessel on the right → carries blood to the heart → this is a vein
- A network of tiny vessels in the middle → capillaries

Labels to drag:
- "from heart" → red vessel (artery)
- "to heart" → blue vessel (vein)
- "artery" → red vessel
- "vein" → blue vessel
- "capillaries" → the network in the middle

So, the correct labels are:

- Top left box (above red vessel): artery
- Middle top box (above capillary network): capillaries
- Right top box (above blue vessel): vein
- Left side of red vessel: from heart
- Right side of blue vessel: to heart

✔ So the labeled diagram should be:

```
[artery] [vein]
↓ ↑
[from heart] ← artery → capillaries → vein → [to heart]
```

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🔹 Now, let's answer the questions:

#### 1. What blood vessel with thick muscular wall and narrow lumen takes away the blood from the heart?

✔ Artery
→ Arteries have thick muscular walls and narrow lumens to withstand high pressure as they carry blood *away* from the heart.

> ✔ Answer: Artery

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#### 2. The arteries have valves:

✘ False
→ Arteries do not have valves. Valves are found in veins to prevent backflow.

> ✔ Answer: False

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#### 3. The largest artery is the ___ .

✔ Aorta
→ The aorta is the largest artery; it branches off from the left ventricle of the heart.

> ✔ Answer: Aorta

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#### 4. The artery carries ______ blood to all the different parts of the body.

✔ Oxygenated (for systemic circulation)
→ Arteries carry oxygen-rich blood from the heart to the body (except pulmonary arteries).

> ✔ Answer: oxygenated

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#### 5. What blood vessel with thin muscular walls and large lumen takes blood towards the heart?

✔ Vein
→ Veins have thinner walls and larger lumens than arteries. They carry blood back to the heart.

> ✔ Answer: Vein

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#### 6. Veins have valves to prevent back flow.

✔ True
→ Yes, veins have one-way valves to help blood return to the heart against gravity.

> ✔ Answer: True

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#### 7. The largest vein is the ___ .

✔ Vena cava
→ The superior and inferior vena cava are the largest veins, returning blood to the heart.

> ✔ Answer: Vena cava

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#### 8. The smallest blood vessel is ___ . It has one cell thick walls and very small lumen.

✔ Capillary
→ Capillaries are microscopic vessels with single-cell-thick walls for efficient exchange.

> ✔ Answer: Capillary

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#### 9. Capillaries carry blood at ___ pressure.

✔ Low
→ Pressure drops significantly by the time blood reaches capillaries due to resistance in arteries and arterioles.

> ✔ Answer: low

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#### 10. The blood vessel where gases, nutrients and wastes are exchanged.

✔ Capillaries
→ Exchange happens across capillary walls due to their thinness and proximity to tissues.

> ✔ Answer: Capillaries

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#### 11. The walls of the capillaries are ___ to allow easy diffusion of gases, nutrients.

✔ Thin or one cell thick
→ This allows rapid diffusion of substances between blood and tissues.

> ✔ Answer: thin (or one cell thick)

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✔ Final Answers Summary:

| Question | Answer |
|--------|--------|
| 1 | Artery |
| 2 | False |
| 3 | Aorta |
| 4 | Oxygenated |
| 5 | Vein |
| 6 | True |
| 7 | Vena cava |
| 8 | Capillary |
| 9 | Low |
| 10 | Capillaries |
| 11 | Thin (or one cell thick) |

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📌 Additional Notes:

- Arteries: Thick walls, high pressure, carry blood away from heart.
- Veins: Thin walls, valves, low pressure, carry blood toward heart.
- Capillaries: Site of exchange, extremely thin walls.

Let me know if you'd like this turned into a printable answer key!