Respiration and Photosynthesis

1. Energy Transformations

2. Some Types of Energy
S.H.E.L.P.A.C.K.E. Sound, Heat, Electrical, Light, Potential, Atomic, Chemical, Kinetic, Elastic
• Potential: the energy stored up before it is used
Example: Gravitational Potential energy when you lift something up
• Kinetic: movement energy
Example: falling, moving, speeding up
• Chemical: energy stored in chemical bonds
Example: Food, petrol, muscles before they do work
• Light: Electromagnetic radiation of a wavelength
that can be seen by the human eye.
• OTHERS: heat, sound, electrical, atomic, elastic

3. Warm Up!
1. What does the word “cycle” mean?
• Tell your partner an example.
2. What does the word, “recycle” mean?
• Tell your partner about a time you “recycled”
3. Draw your story in the form of a cycle

4. Learning Objectives
• 1. Define and identify autotrophs(producers)
and heterotrophs(consumers)
• 2. Give examples of how energy is recycled in
the environment, in ecosystems, between
organisms, and within an organism.

5. Energy Transfers (Cycles)
• Within the environment
• Within an ecosystem
• Between organisms
• Within an organism

6. Group Task
• 1. You will be working in groups of 4. The groups will be
made for you.
• 2. Each member of the group will be in charge of one
type of ‘energy transfer’ (previous slide)
• 3. Your job is to find examples of each energy transfer.
For example, if you are doing ‘transfers in the
environment’, you can discuss the water cycle.
• 4. Identify the reactants and products in the cycle.
• 5. Record your answers on the chart paper. 

7. Obtaining Food
All organisms need food for energy and building materials.
Biologists classify organisms according to how they obtain food.
Autotrophs are organisms such as a
plant that makes its own food.
For example, during photosynthesis
plants use the sun's energy to
convert water and carbon dioxide
into sugars.
Autotrophs are also called
producers.
Heterotrophs are organisms that
cannot make their own food, such as
humans, meaning "other eaters."
Heterotrophs are also called
consumers.

8. Autotrophs and Heterotrophs
1. Identify the autotrophs and heterotrophs in
your cycles!
2. Thinking ahead. Can you identify the type of
energy that the autotrophs and heterotrophs
use?
3. Were there other forms of energy within
your cycles? (think back to our last lesson on
types of energy)

9.  Organic molecules are a source of energy and building
materials for organisms
 How do organisms harvest (get/obtain) the energy from
foods?
 They use cellular respiration
 Definition
 Cellular respiration is a chemical process that uses oxygen
to convert the chemical energy stored in organic
molecules into another form of chemical energy
 It produces a molecule called….
 ATP or adenosine triphosphate
Harvesting the energy in food

11. • Cells in plant and animals use ATP as their
main energy supply
• The process of cellular respiration produces
Co2 as waste product.
• In cellular processes there is a constant cycling
of chemical ingredients.
• ‘Cycling’, in this case, means that the
ingredients are used to make a product and
the product is used to make the ingredients.
Harvesting the energy in food

12. Energy flow occurs through
the ecosystem.
Sun is the primary source
of energy for all living
thing.
The products of photosynthesis
are the reactants for cellular
respiration, while the products
of cellular respiration are the
reactants for photosynthesis.
Principles of Energy Harvest

13. Cycling of chemicals

14.  Energy is the ability to do work.
 Two basic types of energy are
1. Kinetic energy 2. Potential energy
 Kinetic energy is the energy of moving
things…examples: running, walking, cycling
 Potential energy is energy that is stored due to a
body’s position or arrangement e.g. standing
poised on top of a ski slope, diving board,
standing on top of stairs
Energy types

16. Warm Up!
Think Back to your unit on Biomolecules:
Lipids, Proteins, Carbs, and Nucleic Acids
1. What were the
monomers/building
blocks for each
group?
2. What process breaks
down biomolecules
in the body into their
monomers?
3. When you read the
label on a food item,
what is the unit used
to measure energy?

17. Objectives
1.Define “calorie”
2.List the ingredients(reactants) and products
needed for Cellular Respiration to occur
3.Explain how the energy obtained from food drives
cellular respiration to occur

18. Calories: Units of Energy
calorie: amount of energy required to raise the temperature of 1 g of water 1 oC.
The "calories" shown on a food label are actually kilocalories. One kilocalorie
(kcal) equals 1000 calories.
What factors contribute to the energy
(calorie) needs of a person?

19. Chemical Energy
• Just like the molecules in
gasoline and other fuels,
organic compounds have a
form of potential energy
called chemical energy.
• The stored chemical
energy of foods such as
peanuts can be released
through cellular
respiration.

20. The chemical energy stored in peanuts
Fats
carbohydrates
proteins
Respiration in
Mitochondria

21. • In your cells, molecules such as glucose react with oxygen during
cellular respiration
• They produce waste in the form of carbon dioxide and water
• Cells convert about 40% of the energy found in food into useful
work.
• Where does the rest go?
• It is converted to thermal energy.
• This is lost from your body as heat
How do we use the energy found in food?
Respiration in
Mitochondria

22. Journal #1
Questions:
• 1. Identify the types of energy you have at the top of
a staircase and as you go down the stairs.
• 2. How does you body use chemical energy during
exercise?
• 3. If a food has 10kcal of energy, how much could it
increase the temperature of 100g of water?

23. Warm Up 2!
• What does ATP stand for?
-Write it down
• What is another word for ATP?
-Write it down
• Where do we get ATP from?
-Write it down
• What organelle makes ATP in the cell?
-Write it down

24. ATP has Potential Energy
• What is ATP made of?
• How is this Potential Energy Released?

25. ATP provides the energy for cellular work
ATP: (Adenosine triphosphate) main energy source that cells use for most of
their work
An ATP molecule contains potential energy, much like a compressed spring.
When a phosphate group is pulled away during a chemical reaction, energy is
released.

26. The ATP Cycle
ATP is constantly recycled in your cells. A working muscle cell recycles all of its
ATP molecules about once each minute. That's 10 million ATP molecules spent
and regenerated per second!

27. ATP and Cellular Work
Cells perform three main
types of work:
• chemical work
• mechanical work
• transport work
The transfer of the phosphates
from ATP forming ADP
provides the energy.

28. Relationship of Cellular Respiration to Breathing
Cellular respiration is an aerobic process, meaning that it requires oxygen
Breathing supports cellular respiration by providing the body with oxygen and
removing carbon dioxide.

29. Overall Equation for Cellular Respiration
In cellular respiration, the atoms in glucose and oxygen are rearranged, forming
carbon dioxide and water. The cell uses the energy released to produce ATP.

30. Cellular respiration breaks down organic molecules to yield energy.
Energy stored in organic compounds is released in a series of enzymes
controlled reactions.
Word equation for respiration :
Glucose + Oxygen Carbon dioxide + Water + Energy
Chemical Equation

31. Journal #2
Questions:
1. In what way is ATP like a compressed spring?
2. List 3 main types of cellular work
3. What is the source of energy for regenerating ATP from
ADP?
4. How is breathing similar and different to cellular
respiration?
5. Write the equation for cellular respiration. What are the
reactants? What are the products?
6. For each sugar molecule that you consume, how many ATP
molecules are produced?

32. CELLULAR RESPIRATION
CONVERTING YOUR FOOD ENERGY TO ATP, ONE
GLUCOSE MOLECULE AT A TIME

33. TURN THOSE FROWNS UPSIDE DOWN,
YOU WILL LOVE THIS TOPIC!

34. WARM UP!
• What is another name for sugar?
• Recall the meaning of ‘’lysis”. What does it stand
for?
• What comes to mind when you think of respiration?
• What organelle is responsible for making energy in
the cell?

35. WHERE DOES IT TAKE PLACE?
In Eukaryotic Cells, the reactions of Aerobic Respiration occur
Inside MITOCHONDRIA.

36. Cellular Respiration (CR)
• There are many chemical reactions taking place in
the cell
• All the chemical reactions happening in the cell
make up the cell’s metabolism
• CR is made up of a series of reactions
• It is called a metabolic pathway
• An enzyme acts on each reaction in the pathway
• There are three stages in the metabolic pathway
of cellular respiration:
1. Glycolysis
2. Krebs cycle
3. Electron Transport Chain

38. Respiration involves Glycolysis, the Krebs cycle, and the Electron
transport chain:

39. Structure of Mitochondria
Mitochondria are found in almost all eukaryotic cells. Its structure is key to its role
in cellular respiration.
It’s complex folding pattern of membranes and spaces allows for many sites where
reactions can occur.

40. At the end of Glycolysis…
90% of energy in glucose still
unused!
How do we get the rest of the energy?

41. Stage 2: The Krebs Cycle
The Krebs cycle finishes the breakdown of pyruvic acid molecules to carbon dioxide,
releasing more energy in the process. The enzymes for the Krebs cycle are dissolved in
the fluid matrix within a mitchondrion's inner membrane.

42. Stage 3: The Electron Transport Chain

43. Web resources
• http://leavingbio.net/respiration-
(higher%20level).htm
• http://www.sumanasinc.com/webcontent/ani
mations/content/cellularrespiration.html

44. From 1 molecule of glucose…
…38 ATPs!!! (as 2 are used, we sometimes say 36)

45. • What happens when you do too much exercise?
• You get a cramp or sore muscles
• This happens because your lungs can’t provide oxygen to
your muscles quick enough
• This process is called fermentation
• This process makes ATP without using oxygen
• In fermentation a waste product called lactic acid is
produced.
• This type is Lactic acid fermentation.
• Therefore, the soreness is caused by an accumulation of
lactic acid in the muscle cells.
Anaerobic Respiration:
Some cells harvest energy
without Oxygen

46. • Like muscle cells, YEAST is able to carry out
cellular respiration and fermentation
• When yeast is kept in an anaerobic environment
they ferment sugar.
• This produces alcohol instead of lactic acid as a
waste product.
• This is called alcoholic fermentation
• It also produces Co2 as a waste product
• Used to make beer and wine
• Bacteria are also used to make cheese and yogurt
Fermentation in microorganisms

47. Journal #3
Summary 32 - 46
Questions:
1. What is the 3rd stage of cellular respiration?
2. Why are electrons important in cellular respiration?
3. Falling Electrons release_______________
4. An accumulation of electrons are used to produce _________
5. The 3rd Stage produces _________and ________
6. What is the total amount of ATP molecules formed from 1
glucose molecule?
7. If there is a lack of oxygen when harvesting energy, what
process occurs?
8. Explain why you may feel sore after physical activity.
9. Beer, wine and cheese are all examples of? Why?

48. • Photosynthesis is the process by which plants
convert the energy of sunlight into organic
molecules such as glucose
• This takes place in the chloroplast
• Chloroplasts contain a green pigment called
chlorophyll
• In a plant most chloroplasts are found in a layer
called the mesophyll
• Pores on the underside of the leaf called stomata
allow Co2 to enter and….
• Oxygen to leave
Photosynthesis

49. • Like a mitochondria, a
chloroplast has an inner
and outer membrane
• Inside is a thick fluid called
stroma
• In the stroma are disk-
shaped sacs called
thylakoids
• These thylakoids are
stacked into grana
Chloroplasts

50. • What is the equation for photosynthesis?
• 6CO2 + 6H2O C6H1206 + 6O2
• There are 2 main stages in photosynthesis
• The light reactions and the Calvin cycle
Photosynthesis
Light &Chlorophyll

51. • These reactions convert sunlight into chemical
energy
• Molecules in the membranes of the thylakoids
are very important
• First of all chlorophyll captures the light
• It uses this energy to split water into….
• Hydrogen and oxygen
• Oxygen is a waste product of photosynthesis
• It escapes into the atmosphere through the
stomata
The light reactions

52. • The hydrogen and electrons are used to make NADPH an
electron carrier. Light is also used to make ATP
The light reactions

53. Journal #4
Summarize Slides 48 - 52
• Are plants autotrophs or heterotrophs?
• What are the two stages of photosynthesis?
• What are the reactants of photosynthesis?
• What are the products of photosynthesis?
• How is photosynthesis similar to cellular
respiration?
• What is the role of glucose in photosynthesis
and respiration?