Diffusion and Osmosis Worksheet with examples and diagrams.
A worksheet titled "Diffusion and Osmosis Worksheet" with questions and diagrams illustrating molecular movement across cell membranes, including examples of diffusion and osmosis in everyday scenarios and a diagram showing the direction of diffusion.
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Step-by-step solution for: Diffusion and osmosis collection | Worksheetzone
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Show Answer Key & Explanations
Step-by-step solution for: Diffusion and osmosis collection | Worksheetzone
You're right to ask for an explanation — let’s go through each question on this Diffusion and Osmosis Worksheet step by step, so you understand *why* each answer is correct.
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## 🔬 Key Concepts First:
- Diffusion: The movement of molecules (usually gases or solutes) from an area of high concentration to an area of low concentration. It does not require a membrane (though it can happen across one), and it doesn’t involve water as the main moving substance.
- Osmosis: A special type of diffusion — it’s the movement of water across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration (or equivalently, from high water concentration to low water concentration).
> 💡 Think: Diffusion = particles moving; Osmosis = water moving to balance solutes.
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## ✔ Question-by-Question Breakdown:
→ Answer: Diffusion
Why? Smell molecules (from sweat) are spreading through the air from the student (high concentration) to you (low concentration). No membrane involved — just particles moving in air → Diffusion.
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→ Answer: Osmosis
Why? Your skin cells are surrounded by water (hypotonic environment). Water moves *into* your skin cells via osmosis, causing them to swell. But because the outer layer of skin (keratin) doesn’t expand easily, it wrinkles → Osmosis.
> 🧠 Note: Some people think it’s “water entering skin” → yes, but that’s osmosis because it’s water moving across cell membranes due to solute imbalance.
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→ Answer: Diffusion
Why? Perfume molecules spread through the air from her (high concentration) to you (low concentration). Again, no membrane — just gas molecules moving → Diffusion.
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→ Answer: Osmosis
Why? Salt creates a hypertonic environment outside the slug’s body. Water inside the slug’s cells moves *out* through osmosis to try to dilute the salt → cells lose water → slug shrivels → Osmosis.
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→ Answer: Diffusion
Why? Smell molecules (from food) travel through air → high concentration near grill → low concentration where you are → Diffusion.
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→ Answer: Osmosis
Why? Salt water is hypertonic compared to your throat cells. Water leaves the cells via osmosis → cells shrink → reduces swelling → Osmosis.
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→ Answer: Diffusion
Why? Oxygen moves from high concentration (in alveoli) to low concentration (in blood capillaries). It crosses membranes, but it’s oxygen molecules moving — not water → Diffusion.
> 📌 Important: Even if it crosses a membrane, if it’s not water moving to balance solutes, it’s still diffusion.
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→ Answer: Osmosis
Why? Vegetables are often dehydrated. Spraying water creates a hypotonic environment. Water enters plant cells via osmosis → cells become turgid → veggies look plump → Osmosis.
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→ Answer: Osmosis
Why? Raisins are dried grapes — very concentrated sugar inside. Water moves into them from the glass (low solute) to the raisin (high solute) → plumps them up → Osmosis.
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## 🎯 Question 10: Use arrows to indicate direction of diffusion
You’re told:
- ○ = molecule that can pass through membrane
- □ = cell membrane
In both diagrams, molecules move from high concentration to low concentration.
- More circles inside the box than outside → molecules will diffuse OUT of the box.
- Arrows should point outward from the box.
✔ Correctly shown in image: arrows pointing out.
- More circles outside the box than inside → molecules will diffuse IN to the box.
- Arrows should point inward.
✔ Correctly shown in image: arrows pointing in.
> ✔️ This is classic passive diffusion — no energy needed, follows concentration gradient.
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## 🍬 Question 11: Net movement of sugar into or out of the cell
Assume sugar can pass through membrane.
Remember: Sugar moves from high concentration to low concentration.
- Inside: 1% sugar
- Outside: 5% sugar
→ Sugar is higher outside → sugar moves INTO the cell.
✔ Arrow pointing in → Correct.
- Inside: 3% sugar
- Outside: 1% sugar
→ Sugar is higher inside → sugar moves OUT of the cell.
✔ Arrow pointing out → Correct.
- Inside: 1% sugar
- Outside: 1% sugar
→ Equal concentration → No net movement.
✔ Arrow should be double-headed or none — but here, they drew a double arrow (up and down) → indicates equilibrium → Correct.
> 📌 Note: In real life, molecules still move randomly, but there’s no *net* movement when concentrations are equal.
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## ✔ Final Summary:
| Question | Answer | Reason |
|----------|------------|--------|
| 1 | Diffusion | Smell molecules spreading in air |
| 2 | Osmosis | Water entering skin cells |
| 3 | Diffusion | Perfume molecules diffusing in air |
| 4 | Osmosis | Water leaving slug cells |
| 5 | Diffusion | Food smell diffusing through air |
| 6 | Osmosis | Water leaving throat cells |
| 7 | Diffusion | Oxygen moving across membranes (not water) |
| 8 | Osmosis | Water entering veggie cells |
| 9 | Osmosis | Water entering raisins |
| 10A | Out | Molecules move from high to low concentration |
| 10B | In | Molecules move from high to low concentration |
| 11 Left | In | Sugar moves from 5% → 1% |
| 11 Mid | Out | Sugar moves from 3% → 1% |
| 11 Right | Equilibrium| Same concentration → no net movement |
---
## 🧠 Pro Tip:
To remember the difference:
> Diffusion = Dispersing particles (any molecule)
> Osmosis = Only Water moving across a membrane to balance solutes
---
Let me know if you want a printable version or flashcards for these concepts! 😊
---
## 🔬 Key Concepts First:
- Diffusion: The movement of molecules (usually gases or solutes) from an area of high concentration to an area of low concentration. It does not require a membrane (though it can happen across one), and it doesn’t involve water as the main moving substance.
- Osmosis: A special type of diffusion — it’s the movement of water across a semi-permeable membrane from an area of low solute concentration to an area of high solute concentration (or equivalently, from high water concentration to low water concentration).
> 💡 Think: Diffusion = particles moving; Osmosis = water moving to balance solutes.
---
## ✔ Question-by-Question Breakdown:
1. The student sitting next to you just came from gym class and forgot to shower and you can tell.
→ Answer: Diffusion
Why? Smell molecules (from sweat) are spreading through the air from the student (high concentration) to you (low concentration). No membrane involved — just particles moving in air → Diffusion.
---
2. After sitting in the bathtub for hours, your fingers start to look like prunes.
→ Answer: Osmosis
Why? Your skin cells are surrounded by water (hypotonic environment). Water moves *into* your skin cells via osmosis, causing them to swell. But because the outer layer of skin (keratin) doesn’t expand easily, it wrinkles → Osmosis.
> 🧠 Note: Some people think it’s “water entering skin” → yes, but that’s osmosis because it’s water moving across cell membranes due to solute imbalance.
---
3. The girl sitting two rows ahead of you put on too much perfume this morning.
→ Answer: Diffusion
Why? Perfume molecules spread through the air from her (high concentration) to you (low concentration). Again, no membrane — just gas molecules moving → Diffusion.
---
4. One way to get rid of slugs in your garden is to sprinkle salt on them, so they shrivel up.
→ Answer: Osmosis
Why? Salt creates a hypertonic environment outside the slug’s body. Water inside the slug’s cells moves *out* through osmosis to try to dilute the salt → cells lose water → slug shrivels → Osmosis.
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5. Yum! Something smells good. The neighbors are cooking on the grill!
→ Answer: Diffusion
Why? Smell molecules (from food) travel through air → high concentration near grill → low concentration where you are → Diffusion.
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6. Gargling with salt water when you have a sore throat causes your swollen throat cells to shrink and feel better.
→ Answer: Osmosis
Why? Salt water is hypertonic compared to your throat cells. Water leaves the cells via osmosis → cells shrink → reduces swelling → Osmosis.
---
7. Oxygen molecules move from the air sacs in the lungs across the cell membranes into the blood.
→ Answer: Diffusion
Why? Oxygen moves from high concentration (in alveoli) to low concentration (in blood capillaries). It crosses membranes, but it’s oxygen molecules moving — not water → Diffusion.
> 📌 Important: Even if it crosses a membrane, if it’s not water moving to balance solutes, it’s still diffusion.
---
8. Robert sprays water on the veggies in the produce section to “plump them up”.
→ Answer: Osmosis
Why? Vegetables are often dehydrated. Spraying water creates a hypotonic environment. Water enters plant cells via osmosis → cells become turgid → veggies look plump → Osmosis.
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9. You put raisins in a glass of water and they plump up.
→ Answer: Osmosis
Why? Raisins are dried grapes — very concentrated sugar inside. Water moves into them from the glass (low solute) to the raisin (high solute) → plumps them up → Osmosis.
---
## 🎯 Question 10: Use arrows to indicate direction of diffusion
You’re told:
- ○ = molecule that can pass through membrane
- □ = cell membrane
In both diagrams, molecules move from high concentration to low concentration.
A)
- More circles inside the box than outside → molecules will diffuse OUT of the box.
- Arrows should point outward from the box.
✔ Correctly shown in image: arrows pointing out.
B)
- More circles outside the box than inside → molecules will diffuse IN to the box.
- Arrows should point inward.
✔ Correctly shown in image: arrows pointing in.
> ✔️ This is classic passive diffusion — no energy needed, follows concentration gradient.
---
## 🍬 Question 11: Net movement of sugar into or out of the cell
Assume sugar can pass through membrane.
Remember: Sugar moves from high concentration to low concentration.
Left Cell:
- Inside: 1% sugar
- Outside: 5% sugar
→ Sugar is higher outside → sugar moves INTO the cell.
✔ Arrow pointing in → Correct.
Middle Cell:
- Inside: 3% sugar
- Outside: 1% sugar
→ Sugar is higher inside → sugar moves OUT of the cell.
✔ Arrow pointing out → Correct.
Right Cell:
- Inside: 1% sugar
- Outside: 1% sugar
→ Equal concentration → No net movement.
✔ Arrow should be double-headed or none — but here, they drew a double arrow (up and down) → indicates equilibrium → Correct.
> 📌 Note: In real life, molecules still move randomly, but there’s no *net* movement when concentrations are equal.
---
## ✔ Final Summary:
| Question | Answer | Reason |
|----------|------------|--------|
| 1 | Diffusion | Smell molecules spreading in air |
| 2 | Osmosis | Water entering skin cells |
| 3 | Diffusion | Perfume molecules diffusing in air |
| 4 | Osmosis | Water leaving slug cells |
| 5 | Diffusion | Food smell diffusing through air |
| 6 | Osmosis | Water leaving throat cells |
| 7 | Diffusion | Oxygen moving across membranes (not water) |
| 8 | Osmosis | Water entering veggie cells |
| 9 | Osmosis | Water entering raisins |
| 10A | Out | Molecules move from high to low concentration |
| 10B | In | Molecules move from high to low concentration |
| 11 Left | In | Sugar moves from 5% → 1% |
| 11 Mid | Out | Sugar moves from 3% → 1% |
| 11 Right | Equilibrium| Same concentration → no net movement |
---
## 🧠 Pro Tip:
To remember the difference:
> Diffusion = Dispersing particles (any molecule)
> Osmosis = Only Water moving across a membrane to balance solutes
---
Let me know if you want a printable version or flashcards for these concepts! 😊
Parent Tip: Review the logic above to help your child master the concept of osmosis and diffusion worksheet.
