1. PHOTOSYNTHESIS CELLULAR RESPIRATION
Plants are called autotrophs since they make their own food using photosynthesis.
Animals are called heterotrophs since they need to eat (consume) their food.

2. Photosynthesis
Plants break the water and carbon dioxide apart to make new molecules.
6H2O + 6CO2 get rearranged into C6H12O6 + O2

3. Photosynthesis Chemical Equation

4. Balanced Chemical Equation
6CO2 + 6H2O  6O2 + C6H12O6
Atoms are neither created nor destroyed, they are just transferred.
This transferring of atoms is called the Law of Conservation of Matter.

5. Adenosine Triphosphate (ATP)
Nucleic Acid
Structure:
Phosphate group
5 carbon sugar (ribose)
Nitrogenous base (adenine)
Function: Energy

6. Why ATP? An analogy to money…
Glucose in our food is a great source of energy! ($100 bill)
However, individual cell processes may only require a small amount of energy ($1 bill)
Analogy: most vending machines do not accept $100 bills! We need a smaller form of “currency” for these processes.
ATP (adenosine triphosphate) is this important cellular “currency” for life.
ATP releases more appropriate amounts of energy for the individual cellular processes that require energy.
(We will study this molecule in detail in our next activity!)

7. ATP and ADP Cycle ATP = Adenosine triphosphate = 3 phosphates
ADP = Adenosine diphosphate = 2 phosphates
The chemical energy in food is used to make ATP.

8. Energy Review Where does ATP come from and how is it made?
ATP supplies most of the energy that drives metabolism in living things
ATP releases energy when converted into ADP
Where does ATP come from and how is it made?

9. How do cells get their energy?
Cells perform cellular respiration to make ATP.
Analogy: A fully charged battery

10. Cellular Respiration
Cells have mitochondria that perform cellular respiration to make ATP.

11. Cellular Respiration
Living things get most of the energy they need from glucose.
Autrotrophs make glucose using photosynthesis
Heterotrophs get glucose from food they eat
Cellular Respiration
The process that releases energy by breaking down glucose and other food molecules in the presence of oxygen.

12. Cellular Respiration Reactants
Inputs of cellular respiration are oxygen and glucose.

13. Cellular Respiration Products
Outputs of cellular respiration are carbon dioxide, water, and ATP.

14. Cellular Respiration Overview
Cellular Respiration Overall Equation
6O2 + C6H12O6  6CO2 + 6H2O + Energy
The main form of energy produced = ATP

15. Do only animal cells perform cellular respiration?
The BIG Question is…
Do only animal cells perform cellular respiration?
Or do plant cells too?
Only plants perform photosynthesis
Plants AND animals perform cellular respiration!
Can you explain why??

16. Think, Pair, Share
If plant cells need oxygen gas and glucose to make ATP, where do they get them?

17. If plant cells need oxygen gas and glucose to make ATP, where do they get them?
Plants will perform photosynthesis to make the food (glucose) required to do cellular respiration.
Plants also use glucose to make other molecules.

18. Recall from last unit…
What was the organelle that plant cells have for energy that animal cells do not have?

19. Photosynthesis
Plant cells have CHLOROPLASTS that perform photosynthesis to make glucose (sugar).

20. Photosynthesis Reactants
Inputs of photosynthesis are carbon dioxide, water, and light energy.

21. Photosynthesis Products
Outputs of photosynthesis are oxygen and glucose (sugar).

22. Photosynthesis Overview
Photosynthesis Overall Equation
Light Energy + 6CO2 + 6H2O  6O2 + C6H12O6

23. PLANTS and ANIMALS need each other.
Plants take in water and carbon dioxide in order to perform photosynthesis to make glucose and oxygen gas.
Animals take in oxygen gas and glucose to make water and carbon dioxide.

24. Site of Cellular Respiration
Plant and animal cells contain mitochondria: cell structures that transform chemical energy from glucose to ATP.

25. Glycolysis Glyco = Glucose lysis = Breakdown
Occurs in the cytoplasm of the cell
Molecules of GLUCOSE are broken down into 2 molecules of Pyruvic Acid.
Cell must use (invest) 2 ATP
Produces Energy Carrier Molecules
4 ATP
2 NADH

26. Mitochondria
The mitochondria is the organelle where the final stages of cellular respiration occurs.
Kreb’s Cycle
Electron Transport Chain
Cells that use a lot of energy have high numbers of mitochondria.
Example: Muscle cells in the heart!!

27. Kreb’s Cycle Aerobic Process = Only if oxygen is present!!
Occurs in the MATRIX of the mitochondria
Pyruvic Acid from Glycolysis enters to form
1 ATP
3 NADH
1 FADH2
CO2 (which is released when we exhale!!)
Also called the Citric Acid Cycle

28. Electron Transport Chain
Energy carrier molecules produced during Glycolysis and the Kreb’s Cycle enter the ETC
NADH
FADH2
Occurs in the folds of the Inner Membrane of the Mitochondria
The electrons are passed down a chain of proteins until they reach the final electron acceptor…..oxygen!
So this step is aerobic (requires oxygen)
The ETC produces 32 ATP and H2O

29. Significant ATP Production
Aerobic cellular respiration releases energy SLOWLY, using oxygen to convert ONE molecule of glucose to 36 ATP!

30. Cellular Respiration Flowchart
Section 9-2
Glucose (C6H1206) +
Oxygen (02)
Glycolysis
Krebs Cycle
Electron Transport Chain
Carbon
Dioxide
(CO2) +
Water
(H2O)
Process requires the presence of oxygen.
This is called aerobic respiration.

31. Electron Transport Chain
  Cellular Respiration: Overview
Mitochondrion
Electrons carried in NADH
Electrons carried in NADH and FADH2
Pyruvic acid
Glucose
Electron Transport Chain
Krebs Cycle
Glycolysis
Mitochondrion
Cytoplasm

32. Aerobic Respiration – Equation
C6H12O6 + 6 O H2O + 6 CO ATP
food
(glucose, a carbohydrate)
oxygen
water
carbon
dioxide
Does this look familiar?

33. Aerobic Training Ex: long runs, biking, swimming
Can increase the size and number of mitochondria in muscle cells
Can increase the delivery of O2 to muscles by improving the heart and lungs

34. Think, Pair, Share What happens if no oxygen is available?
The Kreb’s Cycle and Electron Transport Chain can’t function!

35. Anaerobic Respiration
What happens when cells don’t have enough oxygen?
Some organisms live in an oxygen-free environment. How do they get their energy?

36. Anaerobic Respiration
Anaerobic respiration is also called fermentation, or the process by which energy is released from glucose when oxygen is NOT available.
This process allows organisms to continue to produce energy until oxygen is available.
However, this process only releases 2 ATP per molecule of glucose.

37. Fermentation The cell can use Fermentation instead!!
Occurs in the Cytoplasm
Just like glycolysis!!
Fermentation
A series of reactions that convert NADH (from glycolysis) back into NAD allowing glycolysis to keep producing a small amount of ATP

38. Two Types of Fermentation
Alcoholic Fermentation
Lactic Acid Fermentation

39. Alcoholic Fermentation
Anaerobic way of converting energy for yeast and other microorganisms.
Yeasts use this process to form ethyl alcohol and carbon dioxide as waste products.
Glucose broken down to produce alcohol, CO2 and energy (ATP)
This causes bread dough to rise
This is how some alcoholic beverages are made
C6H12O6  ethanol + CO2 + 2 ATP

40. Fermentation - Bread Source of sugar? DOUGH! (sugar and/or flour)
Yeast use up the O2 and ferment sugar
Produce CO2, which is trapped within
tiny bubbles & results in the dough rising
Produce ethanol, which evaporates in the baking process

41. Lactic Acid Fermentation
Anaerobic way of converting energy in animal cells and some microorganisms.
Glucose broken down to produce lactic acid, CO2 and energy (ATP).
Occurs in bacteria (unicellular organisms)
This is how cheese, yogurt, and pickles are made.
Occurs in muscles during rapid exercise
When your body runs out of oxygen your muscle cells must produce some ATP using fermentation and glycolysis
Lactic Acid build-up causes muscle soreness or burning after intense activity.
C6H12O6  lactic acid + CO2 + 2 ATP

42. Minimal ATP Production
In the absence of oxygen, anaerobic respiration only releases 2 ATP for each molecule of glucose broken down.

43. Anaerobic Training Ex: sprints, strides, quick bursts of energy
Increase the glycogen levels in the muscles
Increase body’s tolerance to lactic acid

44. Comparing ATP Production
First, your body breaks down glucose through aerobic respiration to produce 36 ATP per glucose molecule; however, this is a slow process.
When muscle cells cannot get enough O2 they break down glucose through lactic acid fermentation to produce 2 ATP per glucose…
Therefore, AEROBIC RESPIRATION is much more efficient in terms of ATP production – ATP compared to 2 ATP!