1. Photosynthesis & Respiration

2. Cells usable source of energy is called ATP
Cell Energy:
Cells usable source of energy is called ATP
ATP stands for adenosine triphosphate
Adenine
Ribose
3 Phosphate groups

3. ADP stands for adenosine diphosphate
Adenine
Ribose
2 Phosphate groups

4. All energy is stored in the bonds of compounds—breaking the bond releases the energy
When the cell has energy available it can store this energy by adding a phosphate group to ADP, producing ATP

5. ATP is converted into ADP by breaking the bond between the second and third phosphate groups and releasing energy for cellular processes.

6. What is Photosynthesis?
The process of photosynthesis is a chemical reaction. It is the most important chemical reaction on our planet.

7. What do plants need for photosynthesis?
Water
Carbon dioxide
Light
chlorophyll

8. Chlorophyll is the pigment inside the chloroplast the absorbs light for photosynthesis
As the chlorophyll in leaves decays in the autumn, the green color fades and is replaced by the oranges and reds of carotenoids.

9. What is the equation for the chemical reaction of photosynthesis?

10. Describe Photosynthesis
The process of changing light energy to chemical energy
Energy stored as sugar
Occurs in plants and some algae
Plants need light energy, CO2, and H2O
Takes place in the chloroplasts, using chlorophyll, the green pigment in plants

11. What is it like inside a chloroplast?
Inside the chloroplasts are stacks of things called thylakoids – they look like smarties.
The part of the chloroplast that is around the thylakoids is called the stroma.
THE CALVIN CYCLE is in the stroma!

13. What are the two types of reactions in photosynthesis?
The first reaction is called light-dependent (occurs in the thylakoids)
The second reaction is light-independent (occurs in the stroma)

14. What do electron carriers do?
Sunlight makes electrons in the chlorophyll (located in the thylakoids) very excited! They are so excited they have to be carried by a special carrier molecule called NADP+
NADP+ carries two electrons at a time.
It also grabs an H+ ion, and this turns the NADP+ into NADPH

15. What does the NADPH do?
The NADPH carries the very excited high-energy electrons to reactions in the cell.
These electrons can be used in making FOOD.
This is the LIGHT-DEPENDENT Reaction

16. What is the dreaded Calvin Cycle?
The Calvin Cycle uses ATP and NADPH from light-dependent reactions to produce high- energy sugars (FOOD)
The Calvin Cycle is a
LIGHT- INDEPENDENT reaction

17. What are the products of photosynthesis?
High-energy sugars (FOOD)
oxygen

18. Why is this important to us?
We cannot make our own food (glucose, energy), we must get our food from plants.
Plants are the first step in the food chain.
The oxygen released during photosynthesis is necessary for all living things.

19. Reactants Diagram H2O CO2 Light Chloroplast C6H12O6 Glucose O2
NADP+
ADP + P
Light
Dependent Reaction
Calvin Cycle
ATP
NADPH
Chloroplast
C6H12O6
Glucose O2
Products

20. Summary:
Light Dependent Reaction—H2O is broken down and light energy is stored temporarily in inorganic energy carriers, ATP and NADPH
Calvin Cycle—energy is transferred from ATP and NADPH to the organic compound glucose

21. Quiz Describe what it’s like inside a chloroplast.
Why is it said that photosynthesis is one of the most important chemical reactions on Earth?
What happens during the Calvin Cycle?
What are the products of photosynthesis?
What is needed for photosynthesis?
What happens to electrons during photosynthesis?
Which happens first, light-dependent reactions or light-independent ones?
What does NADP+ do?

22. What is Cellular Respiration?
Once the energy that was in sunlight is changed into chemical energy by photosynthesis, an organism has to transform the chemical energy into a form that can be used by the organism.
Cellular respiration is the process that releases energy by breaking down food molecules in the presence of oxygen.

23. Describe Cellular Respiration
The breakdown of glucose molecules to release energy
Takes place in all living things
Is a step by step process

24. Where does cellular respiration happen?
In the mitochondria of living things.

26. What is the chemical equation for cellular respiration?

28. Respiration occurs in ALL cells and can take place either with or without oxygen present.

29. What are the Stages of Cellular Respiration?
Glycolysis
The Krebs Cycle
The Electron Transport Chain

30. Aerobic Respiration: requires oxygen
Occurs in the mitochondria of the cell
Total of 36 ATP molecules produced
General formula for aerobic respiration:
C6H12O O CO H2O + 36 ATP
glucose + oxygen carbon dioxide + water + energy
Human cells contain a specialized structure – the mitochondrion – that generates energy.

31. Electron Transport Chain
Diagram
Electrons carried in NADH
Mitochondria
In Cytoplasm
Electrons carried in NADH and FADH2
Krebs Cycle
Electron Transport Chain
Glucose
Glycolysis 2 2 32

32. Anaerobic Processes No oxygen is required for these processes.
Includes glycolysis, the breakdown of glucose, and fermentation.
Some bacteria and yeast are examples of anaerobes.

33. Glycolysis Occurs in the cytoplasm.
Breaks down glucose into 2 molecules of pyruvate
2 ATP molecules are formed.
The series of reactions in which pyruvate is broken down into carbon dioxide is called the Krebs cycle.

35. Yikes! There’s another cycle?
Yes. The Krebs cycle.
The Krebs cycle is where energy is released. Kind of like the Calvin Cycle in reverse…

36. What happens during the Krebs cycle?
Energy is freed from the chemical bonds. The excited electrons are FREEE!
The electrons make ATP.
Carbon dioxide is released. You get rid of it by exhaling…

37. Where do the electrons go?
On the train!
The electrons get to ride the electron transport train, the Final step in the breakdown of glucose.
Point at which ATP is produced

38. What happens to ADP on the train?
Ions rush back and forth and spin the ADP in circles.
This creates enough energy to produce three molecules of ATP per molecule of ADP.
ATP and ADP are special molecules that store energy

39. Summary:
3 steps:
1st glycolysis
2nd Krebs cycle
3rd Electron Transport Chain (ETC)

40. Anaerobic Respiration: occurs when no oxygen is available to the cell (2 kinds: Alcoholic and Lactic Acid)
Also called fermentation
Much less ATP produced than in aerobic respiration

41. Alcoholic fermentation—occurs in bacteria and yeast
Process used in the baking and brewing industry—yeast produces CO2 gas during fermentation to make dough rise and give bread its holes
glucose ethyl alcohol + carbon dioxide + 2 ATP

42. Lactic acid fermentation—occurs in muscle cells
Lactic acid is produced in the muscles during rapid exercise when the body cannot supply enough oxygen to the tissues—causes burning sensation in muscles
glucose lactic acid + carbon dioxide + 2 ATP

43. First step in anaerobic respiration is also glycolysis
Diagram
Anaerobic Respiration
Cytoplasm
Alcoholic fermentation
Bacteria, Yeast 2 ATP
C6H12O6
glucose
glycolysis
Lactic acid fermentation
Muscle cells ATP
ETC
Mitochondria
Krebs Cycle
Aerobic Respiration
36 ATP

44. Diagram of the Process Occurs across Cristae Occurs in Cytoplasm
Occurs in Matrix

45. Quiz 1. Where does cellular respiration take place?
2. What is the chemical equation for cellular respiration?
3. What are the products of cellular respiration?
4. What is the Krebs Cycle?
5. What happens during the Krebs Cycle?
6. What happens to electrons during cellular respiration?
7. How much ATP is produced from one molecule of ADP?

46. Complementary processes
Photosynthesis is an important part of the carbon cycle.
The processes of photosynthesis and cellular respiration are complementary processes, meaning they work together to benefit living organisms.

47. Plants and animals contribute…
Autotrophs, such as plants, produce glucose using the carbon in carbon dioxide.
Both autotrophs and heterotrophs, such as grasshoppers that eat plants, use those carbohydrates in cellular respiration.
Respiration, in turn, produces carbon dioxide.

48. Energy renewal
Energy captured from sunlight by photosynthetic organisms is used and released in the cellular respiration of living things.
The energy that living things use, must continually be renewed through photosynthesis.