Respiration is the process by which glucose and oxygen are combined in the mitochondria of cells to produce energy. The products of respiration are carbon dioxide and water. The balanced chemical equation for respiration is: C6H12O6 + 6O2 → 6CO2 + 6H2O. Practical experiments demonstrated respiration occurring in yeast and humans, such as carbon dioxide production and changes in gas volumes. Factors like oxygen availability can affect the rate of respiration.

1. R E S P I R A T I O N
Settler Activity: Solve the anagram
(rearrange the letters to make one word)
I R O N P I R A T E S

2. The Science
Game

3. Your category is…
Respiration

4. Write a fact about respiration on
your white board
Starter:
You have 2 minutes

5. Hold your boards
up….

6. It happens in your lungs
It produces oxygen
Put your board down if your answer is listed here…
It is to do with breathing X
X
X
Unfortunately, that’s not right. Let’s find out what is…

7. 



It involves glucose and oxygen
It produces carbon dioxide and water
It happens in the mitochondria
if your answer is listed here…
It’s how our cells make energy
Well done

8. Respiration
Learning Outcomes:
By the end of this lesson, you will be able to:
• Write a word equation for respiration (6)
• Explain what respiration is and where it occurs (7)
• Apply your knowledge to plan a practical to investigate variables (8)
Lesson Objectives:
• To understand the process of respiration and the molecules involved
• Carry out practicals to see respiration in action

9. Recap on Animal Cells
(fill in the gaps on your worksheet)
………………………
…..
Controls what
happens in the cell
& contains DNA
………………………
…..
Controls what goes
in and out of the cell
………………………
…..
The powerhouse of
the cell, where
respiration takes
place
………………………
…..
Jelly-like substance
which contains
organelles

10. Recap on Animal Cells
(check your answers)
Nucleus
Controls what
happens in the cell
& contains DNA
Cell Membrane
Controls what goes
in and out of the cell
Mitochondria
The powerhouse of
the cell, where
respiration takes
place
Cytoplasm
Jelly-like substance
which contains
organelles

11. So… What is Respiration?
Fill in the blanks on your worksheet
Respiration is the process by which oxygen and
glucose are combined in the mitochondria of your
cells to produce energy.
The products from this reaction are carbon dioxide
and water.

12. This is why athletes eat
sachets of glucose whilst
running marathons…..

13. So, what is respiration?
How could you write this in a shorter
version?

14. How did you do?
One way to write the process is using the word
equation
glucose + oxygen  carbon dioxide + water + (energy)
Write this down in the space on your worksheet

15. To understand how this works, we need to look at
the chemical elements and molecules involved
How?

16. Using Nano Simbox
1. Collect a tablet, open the web browser
2. Go to: student.nanosimbox.io
3. Enter the software using the code below, your email and name
4. Build Carbon Dioxide, Water, Glucose and Oxygen by pressing the purple icon
with these molecules. Choose the level of difficulty you prefer.
5. Write down the completed chemical formula for each of these molecules on your
worksheet (the letters and numbers)
Code: XXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

17. Let’s try to balance a chemical symbol
equation for respiration
Think of it like a cake – All of the reactants (ingredients) go in, they get
mixed together and chemically joined and become something different,
called the product (the cake in this example)
You know that all the ingredients (2 eggs, 200g flour etc) are in the cake,
but they are now completely different and can no longer be easily
separated.
This is why the equation has to balance.

18. glucose + oxygen  carbon dioxide + water + (energy)
carbon dioxide waterglucose oxygen+ + CO2 H2OC6H12O6 O2
Oxygen always goes around in pairs
unless attached to another element
Word equation for respiration
How do we balanced the symbol equation for Respiration?
Chemical equation for photosynthesis
Energy is not an element, so not
included in the chemical equation
Wait!
We’re not done yet – this equation isn’t balanced –
you need to have the same number of each
element on each side of the equation

19. The rules of balancing equations
C6H12O6 + O2 CO2 + H2O
• Work out how many of each element you have on
each side
• The small number next to an element is how
many of that element there are in that molecule
- You cannot edit this
• You need to work out how many you have to times
an element by to balance it
Let’s put 6 more carbons in to balance both sides
We cannot
separate the
molecule, so….

20. The rules of balancing equations
C6H12O6 + O2 CO2 + H2O
• Work out how many of each element you have on
each side
• The small number next to an element is how
many of that element there are in that molecule
- You cannot edit this
• You need to work out how many you have to times
an element by to balance it
Let’s put 6 molecules of carbon dioxide in
(This also affects
the number of
oxygen molecules
in the equation)

21. The rules of balancing equations
• On this side we have
• 6 x C
• 13 x O
• 2 x H
• On this side we have
• 6 x C
• 8 x O
• 12 x H
C6H12O6 + O2 6CO2 + H2O

22. The rules of balancing equations
• On this side we have
• 6 x C
• 13 x O
• 2 x H
• On this side we have
• 6 x C
• 8 x O
• 12 x H
C6H12O6 + O2 6CO2 + H2O
REMEMBER: You cannot change the small
numbers. Now need 12 x H on the right… We do
this by multiplying the whole H2O molecule

23. The rules of balancing equations
C6H12O6 + O2 6CO2 + 6H2O
• On this side we have
• 6 x C
• 18 x O
• 12 x H
• On this side we have
• 6 x C
• 8 x O
• 12 x H

24. The rules of balancing equations
C6H12O6 + O2 6CO2 + 6H2O
• On this side we have
• 6 x C
• 18 x O
• 12 x H
• On this side we have
• 6 x C
• 8 x O
• 12 x H
Look at the totals below – now we need to
balance the O on the left

25. The rules of balancing equations
C6H12O6 + O2 6CO2 + 6H2O
• On this side we have
• 6 x C
• 18 x O
• 12 x H
• On this side we have
• 6 x C
• 8 x O
• 12 x H
We multiply the O2 by 6…

26. The rules of balancing equations
C6H12O6 + 6O2 6CO2 + 6H2O
• On this side we have
• 6 x C
• 18 x O
• 12 x H
• On this side we have
• 6 x C
• 18 x O
• 12 x H

27. The rules of balancing equations
C6H12O6 + 6O2 6CO2 + 6H2O
• On this side we have
• 6 x C
• 18 x O
• 12 x H
• On this side we have
• 6 x C
• 18 x O
• 12 x H
It matches!
The equation is balanced!

28. The balanced symbol equation for
photosynthesis is:
C6H12O6 + 6O2 6CO2 + 6H2O
Write this on your worksheets

29. Watch the Screaming Jelly Baby
experiment
This shows you just how much
energy is in sugar (glucose)!

30. The power of sugar is AMAZING!

31. Respiration Circus

32. Safety First
• Put your safety goggles on
• Tuck your shirt and tie in
• Tie long hair back




33. There are 4 practicals around the room
Follow the instructions on your worksheet
and note what results you observe

34. Blowing into limewater
What happened?
What does that result mean?
How is this evidence of respiration?

35. Breathing on a mirror
What did you observe?
What product of respiration is demonstrated?

36. Balloon on boiling tube of live
yeast
What happened?
What does this tell you about the state of one
of the products of respiration?

37. Elastic band finger exercise
What happened?
Can you explain why?

38. Anaerobic Respiration
When your mitochondria cannot produce energy as
quickly as the muscles need it – You get anaerobic
respiration.
This is when glucose gets broken down into lactic
acid.
This then breaks down when there is more oxygen,
which is why you breathe faster after exercising.

39. Using Nano Simbox
Find the chemical formula of lactic acid
1. Collect a tablet, open the web browser
2. Go to: student.nanosimbox.io
3. Enter the software using the code below, your email and name
4. Build Lactic Acid. Choose the level of difficulty you prefer.
5. Write down the completed chemical formula for this molecule
on your worksheet (the letters and numbers)
Code: XXXXXXX XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

40. Write the balanced symbol equation
for Anaerobic Respiration
Hint: the work equation is:
Glucose  Lactic Acid (+ Energy)

41. How would you test for
factors affecting the rate of
respiration in yeast?
What factors could you
change?
Plenary:
You have 5 minutes

42. How would you teach
respiration to someone else
in a fun way?
Be creative!
Extension: