# Diffusion and exchange surfaces

Define diffusion and describe the factors affecting it. Explain how diffusion is affected by surface area to volume ratio and relate this to examples of exchange over surfaces in organisms.

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.How would the ratio between 3 and 5 be correctly written?

1/6

Q2.In which two states of matter are particles free to move?

Select two (2) boxes

2/6

Q3.Calculate the surface area of a cube with a side length of 1 cm.

3/6

Q4.Calculate the volume of a cube with a side length of 1 cm.

4/6

Q5. is a gas that is inhaled in the gas exchange system, where it then moves into the blood.

Fill in the blank.

5/6

Q6.Substances move into and out of through the cell membrane.

Fill in the blank.

6/6

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.How would the ratio between 3 and 5 be correctly written?

1/6

Q2.In which two states of matter are particles free to move?

Select two (2) boxes

2/6

Q3.Calculate the surface area of a cube with a side length of 1 cm.

3/6

Q4.Calculate the volume of a cube with a side length of 1 cm.

4/6

Q5. is a gas that is inhaled in the gas exchange system, where it then moves into the blood.

Fill in the blank.

5/6

Q6.Substances move into and out of through the cell membrane.

Fill in the blank.

6/6

# Video

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# Worksheet

These slides will take you through some tasks for the lesson. If you need to re-play the video, click the ‘Resume Video’ icon. If you are asked to add answers to the slides, first download or print out the worksheet. Once you have finished all the tasks, click ‘Next’ below.

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Diffusion and exchange surfaces

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Diffusion is the net movement of particles from an area of high to an area of low .

Fill in the blank.

1/6

Q2.Which of these is an example of diffusion?

2/6

Q3.Diffusion happens quicker at higher temperatures because particles have more energy.

Fill in the blank.

3/6

Q4.Match the adaptation of alveoli to the explanation.
• lots of small air sacs
• one cell thick
• lots of blood vessels
• increases surface area
• short diffusion distance

Where you see this icon you can drag and drop! If you are using your keyboard select and move using space and the arrow keys.

4/6

Q5.Calculate the surface area to volume ratio of a cube with a side length of 10 cm. Give your answer as a decimal and do not include units.

5/6

Q6.Which two of the following are leaf adaptations for diffusion?

Select two (2) boxes

6/6

#### Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

# Diffusion and exchange surfaces

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Diffusion is the net movement of particles from an area of high to an area of low .

Fill in the blank.

1/6

Q2.Which of these is an example of diffusion?

2/6

Q3.Diffusion happens quicker at higher temperatures because particles have more energy.

Fill in the blank.

3/6

Q4.Match the adaptation of alveoli to the explanation.
• lots of small air sacs
• one cell thick
• lots of blood vessels
• short diffusion distance
• increases surface area

Where you see this icon you can drag and drop! If you are using your keyboard select and move using space and the arrow keys.

4/6

Q5.Calculate the surface area to volume ratio of a cube with a side length of 10 cm. Give your answer as a decimal and do not include units.

5/6

Q6.Which two of the following are leaf adaptations for diffusion?

Select two (2) boxes

6/6

# Lesson summary: Diffusion and exchange surfaces

## Time to move!

Did you know that exercise helps your concentration and ability to learn?

For 5 mins...

Move around:
Jog

On the spot:
Chair yoga