1.2 Gas exchange

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

1.2 Gas exchange and respiration

what is air?

what happens during gas exchange?

what is diffusion?

which compound isn't part of the air we breathe?

1. oxygen
2. nitrogen
3. carbon dioxide
4. helium

what is air?

a mixture of....

oxygen, carbon dioxide, nitrogen and water vapour

what happens to these gasses?

which gas isn't used in our body?

1. carbon dioxide
2. oxygen
3. nitrogen
4. water vapour

Written formula

Cellular respiration can be written down as follows:

glucose + oxygen --> water vapour + carbon dioxide + energy

When you burn wood in a campfire, this is called combustion:

wood + oxygen -->  water vapour + carbon dioxide + energy

cellular respiration

glucose + oxygen => water vapour + carbon dioxide + energy

C6H12O6 + 6 O2 => 6 CO2 + 6 H2O + energy

Explain the percentages on page 13. Why do the change during in/exhaling

Energy use 

We use the energy for life processes such as:

• keeping a constant body temperature
  
• movement 
  
• replacing and adding (growing) cells
  

experiment 16 page 13 wb

we read the experiment together

we do the experiment in groups of two

we discuss your results

finish the sentence...
lime water is an indicator for.............

And now..

Make 1.2: exercise: 9, 10, 15, 17, 18, 19 

homework tuesday 14-09: study p13+14 make 9, 10, 15, 17, 18, 19

Lesson plan 14-09

• Discuss homework exercises: 10, 17
  
•  Explanation gas exchange + diffusion 

Gas exchange

Oxygen in the lung capillaries

Carbondioxide out of the lung cappillaries

Process is called diffusion

Diffusion

Diffusion is the movement of particles from an area of higher concentration to areas of lower concentration, until the concentrations in both areas are equal. 

No energy is needed for this process.

explain the meaning of diffusion in your own words

In diffusion a substance moves from ...

1. a high to a low concentration
2. a low to a high concentration

Which change would not speed up diffusion in an animal cell?

1. Make the membrane thinner
2. Move the blood supply closer to the cell
3. Make the cell rounder
4. Increase the concentration gradient

page 16 talking point

fill in the correct answers together with your neighbor

what is osmosis?

homework

• Tuesday (20-09): study pages 15, 16, 17 + make exercises:  12, 13, 14
• Wednesday (21-09): study 1.3 + make exercises 20, 21, 22, 23, 24