04 diffusion - the knowledge curriculum project€¦ · diffusion is the movement of particles...

www.knowledgecurriculum.co.uk KEY FACTS BEFORE YOU START All living organisms are made up of cells. Cells of the same type form tissue. Cells have common elements: cell membrane, cytoplasm, nucleus, vacuole, mitochondria and plant cells also contain cell wall and chloroplasts. INTRODUCTION This topic is about how cells move and how molecules can move between cells. This movement is called diffusion. We are going to look at what diffusion is. We will show it in two different examples and we will explain why diffusion is important in other areas of biology. What is diffusion? Diffusion is the movement of particles (cells or molecules) from an area of high concentration to an area of low concentration. 04 Diffusion 21 20 www.knowledgecurriculum.co.uk Before diffusion After diffusion (equilibrium) Diffusion Diffusion happens in liquids and gases where particles are moving randomly but not in solids. Example 1 Orange Squash Orange squash the ultimate diffusion example. All the molecules are concentrated at the bottom of the glass Water molecules and squash molecules begin to move around the glass The water and the squash molecules have moved into space so they are evenly distributed in the glass What causes diffusion? In gases and liquids, particles move randomly from place to place. The particles collide with each other or with their container. This makes them change direction. Eventually, the particles are spread evenly through the whole container. This is called equilibrium. Example 2 Respiration As we breathe (respiration), air comes into the lungs. Once in the lungs, oxygen is moved into the bloodstream through diffusion. Blood carries the oxygen through the body to where it is needed. The waste product (carbon dioxide) diffuses from red blood cells into the lungs and is expelled. Red blood cells collect carbon dioxide from the body’s cells and transports it back to the lungs. Questions 1) Particles move from areas of __________concentration to ____________ concentration. 2) Circle the two states in which diffusion can occur: SOLID LIQUID GAS 3) Write your own description of diffusion. 4) Oxygen diffuses from the air to the ___________ during respiration.

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Page 1: 04 Diffusion - The Knowledge Curriculum Project€¦ · Diffusion is the movement of particles (cells or molecules) from an area of high concentration to an area of low concentration

www.knowledgecurriculum.co.uk

KEY FACTS BEFORE YOU STARTAll living organisms are made up of cells. Cells of the same type form tissue.Cells have common elements: cell membrane, cytoplasm, nucleus, vacuole, mitochondria and plant cells also contain cell wall and chloroplasts.

INTRODUCTIONThis topic is about how cells move and how molecules can move between cells. This movement is called diffusion. We are going to look at what diffusion is. We will show it in two different examples and we will explain why diffusion is important in other areas of biology.

What is diffusion?Diffusion is the movement of particles (cells or molecules) from an area of high concentration to an area of low concentration.

Diffusion

2 12 0 www.knowledgecurriculum.co.uk

Before diffusion After diffusion (equilibrium)

Diffusion

Diffusion happens in liquids and gases where particles are moving randomly but not in solids.

Example 1Orange SquashOrange squash the ultimate diffusion example.

All the molecules are concentrated at the bottom of the glass

Water molecules and squash molecules begin to move around the glass

The water and the squash molecules have moved into space so they are evenly distributed in the glass

What causes diffusion?

In gases and liquids, particles move randomly from place to place. The particles collide with each other or with their container. This makes them change direction. Eventually, the particles are spread evenly through the whole container. This is called equilibrium.

Example 2RespirationAs we breathe (respiration), air comes into the lungs.

Once in the lungs, oxygen is moved into the bloodstream through diffusion. Blood carries the oxygen through the body to where it is needed.

The waste product (carbon dioxide) diffuses from red blood cells into the lungs and is expelled.

Red blood cells collect carbon dioxide from the body’s cells and transports it back to the lungs.

Questions

1) Particles move from areas of __________concentration to ____________ concentration.

2) Circle the two states in which diffusion can occur: SOLID LIQUID GAS

3) Write your own description of diffusion.

4) Oxygen diffuses from the air to the ___________ during respiration.

Diffusion. Def: the movement of molecules from an area of high concentration to an area of low concentration. No cellular energy is involved (this is

Osmosis, Diffusion, Active Transport. Diffusion, Osmosis and Concentration Gradient Diffusion – the movement of a substance from a high concentration

Osmosis and Diffusion Gummy Bear Lab. Diffusion SOLUTE PARTICLES move from HIGH concentration to LOW concentration. HIGH CONCENTRATION LOW CONCENTRATION