1. Photosynthesis & Cellular Respiration
Cellular Energy Or
Bioenergetics

2. How does energy from the sun become energy for life?

3. Organisms called producers convert light energy to chemical energy using a process called photosynthesis.
Photosynthesis- Amoeba Sisters

4. The chemical energy produced in photosynthesis is in the form of sugar.
This allows producers to store the energy for later use.

5. Photosynthesis
Method of converting sun energy into chemical energy usable by cells
Autotrophs utilize this process
Photoautotrophs- light
Chemoautotrophs- chemicals
Equation
6CO2 + 6H2O + light → C6H12O6 + 6O2

6. Fill It In …
The goal of photosynthesis is …

7. Photosynthesis takes place within the cell
In eukaryotic cells, organelles called chloroplasts are the site of photosynthesis

8. Photosynthesis takes place within the cell
Chloroplasts are filled with a pigment called chlorophyll.
This pigment allows the cell to “gather” energy from light waves.

9. Photosynthesis takes place within the cell
Some prokaryotic cells can photosynthesize, but they do NOT have chloroplasts.
They do, however, contain chlorophyll.

10. CO2 + H2O + sunlight (radiant energy) -> C6H12O6 + O2
Photosynthesis is a metabolic pathway. This means it is a series of chemical reactions. All of these reactions can be simplified into one chemical equation:
CO2 + H2O + sunlight (radiant energy) -> C6H12O6 + O2
(reactants) (products)

11. CO2 + H2O + sunlight (radiant energy) -> C6H12O6 + O2
The reactants (things that are used) for photosynthesis are obtained from the environment.
The carbon dioxide enters the leaves from the air and the water enters the roots from the soil.

12. CO2 + H2O + sunlight (radiant energy) -> C6H12O6 + O2
The products (things that are made) of photosynthesis include sugar and oxygen.
Sugar is stored in the cell and used as food.
Oxygen is released into the air.

13. Electron Carriers
Carrier molecule- a compound that can accept a pair of high-energy electrons and transfer them along with most of their energy to another molecule
Process: electron transport
Molecule: electron transport chain

14. NADP+: NADP+ accepts and holds 2 high-energy electrons along with H+
When this occurs it becomes NADPH
NADPH can then carry high-energy electrons to chemical reactions elsewhere

15. Light-Dependent Reactions
Require light
Produce oxygen gas
Convert ADP and NADP into ATP and NADPH

16. Light-Dependent Reactions
Pigments in photosystem II absorb light
Energy is absorbed by electrons which are passed on to electron transport chain
Electrons come from breaking bonds between water molecules
Create 2 electrons, H+ ions, and oxygen

17. Light-Dependent Reactions
3. Electrons move through electron transport chain
from photosystem II to photosystem I
Energy is used to transport H+ ions from stroma to inner thylakoid
4. Pigments in photosystem I use energy from light to reenergize the electrons
NADP+ picks up high energy electrons and H+ ions
Becomes NADPH

19. Light-Independent Reaction
Calvin Cycle
Uses ATP and NADPH to produce high-energy sugars
Does not require light

20. Calvin Cycle 6 CO2 molecules enter cycle
Combine with 6 5-carbon molecules
Result = 12 3-carbon molecules
2. 3-carbon molecules are converted into higher-energy forms (energy from ATP and NADPH)
carbon molecules are removed from cycle
Used to produce sugars, lipids, amino acids, etc.. For metabolism and growth of plant

21. Calvin Cycle
4. Remaining 10 3-carbon molecules are converted back to 6 5-carbon molecules
Combine with 6 new carbon dioxide molecules to begin the next cycle

22. Factors affecting Photosynthesis
Water
Lack of water can slow or even stop photosynthesis
Desert plants have waxy coating to reduce water loss
Temperature
Enzymes function at particular temp ranges
Intensity of Light
Increasing light increases rate of photosynthesis
There is a maximum rate of photosynthesis

23. Fill It In … Reactants for photosynthesis: 1. 2. 3.
Products of photosynthesis:

24. Photosynthesis provides no DIRECT source of energy for the cell.
The cell must convert the sugar produced to another form of energy: ATP

25. What is ATP, and why should I care?
ATP stands for adenosine triphosphate
This basically means that it is a chemical with three phosphate groups attached.

26. What is ATP, and why should I care?
The cell uses ATP for energy.
ATP is much smaller and faster to use than a larger molecule such as sugar.
The energy in ATP is in the bonds connecting the four parts together.

27. Energy and ATP ATP ADP Adenosine triphosphate
Adenine, 5-carbon sugar, 3 phosphate groups
ADP
Adenosine diphosphate
Adenine, 5-carbon sugar, 2 phosphate groups

28. Fill It In …
ATP is used for …

29. What is ATP, and why should I care?
ENERGY
When the cell needs energy from ATP, it uses enzymes to break the third phosphate off of the molecule.
The energy released is used for things in the cell such as active transport
Removing the third phosphate creates ADP and a loose phosphate

30. What is ATP, and why should I care?
ATP can be recycled.
When more energy is available, a third phosphate is added to ADP to make more ATP.

31. ADP and ATP Storing energy Releasing energy
When a cell has energy available, it can store small amounts by adding a phosphate group to ADP, producing ATP
Releasing energy
Breaking bonds between the 2nd and 3rd phosphate groups
Powers several cellular activities
Active transport, protein synthesis, muscle contraction

32. How do cells use the sugar to make ATP?
Cellular Respiration- Amoeba Sister
All cells must use a process called cellular respiration to create ATP.
Cellular respiration converts sugar (produced in photosynthesis) to create ATP
Cellular respiration takes place in the Mitochondria

33. Fill It In …
The goal of cellular respiration is …

34. Cellular respiration takes place within the cell
In eukaryotic cells, organelles called mitochondria are the sites of cellular respiration

35. Cellular respiration takes place within the cell
Mitochondria use many enzymes to break down sugar (glucose) and store the energy in the chemical bonds of ATP

36. Cellular respiration takes place within the cell
Prokaryotes also use cellular respiration, but the do NOT have mitochondria.
Instead, prokaryotes use parts of their cell membrane.

37. Fill It In …
Types of organisms that use cellular respiration:

38. Cellular respiration is also a metabolic pathway
Cellular respiration is also a metabolic pathway. The simplified equation for cellular respiration is:
C6H12O6 + O2 -> CO2 + H2O + ATP
(reactants) (products)

39. C6H12O6 + O2 -> CO2 + H2O + ATP
The reactants of respiration are glucose and oxygen.
The sugar (glucose) is obtained from the vacuole (in plant cells) or from ingestion (eating) of food.
If oxygen is used, it is obtained from the air.

40. C6H12O6 + O2 -> CO2 + H2O + ATP
The products of respiration are ATP, water, and carbon dioxide.
The water and carbon dioxide are released into the environment as waste products.
ATP is kept in the cell for use as an energy molecule.

41. Cellular Respiration Breakdown of glucose to produce energy
1g of sugar releases 3811 calories of heat energy
Calorie- amount of energy needed to raise the temp of 1g of water 1˚ Celsius
6O2 + C6H12O6 → 6CO2 + 6H2O + energy
Steps:
Glycolysis
Krebs Cycle
Electron Transport Chain

42. Glycolysis
Process in which one molecule of glucose is broken in half, producing 2 molecules of pyruvic acid (3-carbon compound)
In cytoplasm
2 ATP → 4 ATP
NAD+ = electron carrier
Accepts 4 high-energy electrons
Becomes NADH

43. Glycolysis Energy yield is small but happens very fast
Does not require oxygen
Problem: NAD+ molecules fill up with electrons; without NAD+ ATP production stops

44. Fill It In … Reactants of cellular respiration: 1. 2.
Products of cellular respiration: 3.

45. There are two types of cellular respiration: aerobic and anaerobic

46. There are two types of cellular respiration:
Aerobic respiration requires the use of oxygen and makes A LOT of ATP

47. Krebs Cycle
Pyruvic acid is broken down into carbon dioxide in a series of energy-extracting reactions
Aerobic- requires oxygen
AKA citric acid cycle – because citric acid is the first compound produced
In mitochondrion

48. Krebs Cycle

49. Krebs Cycle Pyruvate Oxidation:
Pyruvic acid enters mitochondrion
A carbon atom is removed to form CO2
The other 2 carbon atoms are joined to coenzyme A to form acetyl-CoA
A. Acetyl-CoA adds to a 4-carbon molecule producing a 6-carbon molecule called citric acid

50. Krebs Cycle B. -Citric acid is broken down to produce a 5-carbon chain
- CO2 is released
- electrons transferred to energy carriers
C.- 5-carbon chain is broken down into a 4 carbon chain
- ATP is produced
D. – 4 carbon chain is ready to accept acetyl CoA to start cycle all over
- FAD is converted to FADH2
- NAD+ is converted to NADH

51. Electron Transport Chain
Uses high-energy electrons from the Krebs cycle to convert ADP to ATP
In mitochondrion

52. Electron Transport Chain
A.-NADH and FADH2 are passed along ETC and transfer their electrons down ETC
Eukaryotes: membrane of mitochondrion
Prokaryotes: cell membrane
H+ ions are transferred to intermembrane space
B.-electrons from ETC combine with H+ ions and oxygen to produce H2O

53. Electron Transport Chain
C. Energy is used to transport of hydrogen ions by 2 high-energy electrons
H+ ions build up in the intermembrane space making it positively charged
The other side of the membrane is negatively charged

54. Electron Transport Chain
D.-Inner membranes of mitochondria contain ATP synthase
- ATP spins when H+ ion crosses membrane
- While rotating, the enzyme grabs a low-energy ADP and attaches a phosphate producing ATP

55. Totals Glucose = 2 ATP Krebs + ETC = 34 ATP Total = 36 ATP
Final wastes: water and carbon dioxide

56. There are two types of cellular respiration:
Anaerobic respiration (also called fermentation) takes place when no oxygen is available to the cell and produces very little ATP.
However, this process is much faster than aerobic respiration.

57. Fermentation
Releases energy from food molecules by producing ATP in the absence of oxygen
Anaerobic- not in air
2 main types
Alcoholic fermentation
Lactic acid fermentation
Convert NADH to NAD+
Allows glycolysis to continue producing a steady supply of ATP

58. Alcoholic Fermentation
Pyruvic acid + NADH → alcohol + CO2 + NAD+
Causes bread dough to rise
Yeast in dough runs out of oxygen, begins fermentation which produces CO2

59. Lactic Acid Fermentation
Pyruvic acid + NADH → lactic acid + NAD+
Produced in muscles during rapid exercise when the body cannot supply enough oxygen to the tissues
Some unicellular organisms produce lactic acid as a waste product
Cheese, yogurt, buttermilk, sour cream
Pickles, sauerkraut

60. Fill It In …
Differences in ATP production in aerobic vs. anaerobic respiration:
Aerobic -
Anaerobic -

61. Fill It In …
Anaerobic respiration is also called …

62. Types of anaerobic respiration:
In most microorganisms, fungi, and plant cells, anaerobic respiration produces alcohol as a waste product (alcoholic fermentation)
Alcohol fermentation also produces carbon dioxide gas
Alcohol fermentation occurs in yeast
The carbon dioxide causes dough to rise
The alcohol burns off when the dough is baked

63. Types of anaerobic respiration:
In animal cells, anaerobic respiration produces lactic acid as a waste product (lactic acid fermentation)
This mostly occurs in muscle cells.
Build up of lactic acid causes cramps.

64. Uses for anaerobic respiration

65. A key idea …
Photosynthesis and respiration form a cycle!

66. A key idea …
Photosynthesis and respiration form a cycle!

67. A key idea …
The products from one reaction become the reactants for the other reaction

68. A key idea …
The products from one reaction become the reactants for the other reaction

69. A key idea …

70. Check Yourself!
What pigment AND reactants are required for photosynthesis to occur?
What does photosynthesis produce?
Where does photosynthesis occur in eukaryotic cells?
Where is the energy in ATP stored?
Why does the cell use ATP instead of sugar for energy?
What reactants are required for cellular respiration to occur?
What does cellular respiration produce?
Where does cellular respiration occur in eukaryotic cells?
How is fermentation alike and different from aerobic respiration?

71. Check Yourself!
What pigment AND reactants are required for photosynthesis to occur?
CHLOROPHYLL
CARBON DIOXIDE (CO2)
WATER (H2O)
SUNLIGHT (ENERGY)

72. Check Yourself! What does photosynthesis produce?
GLUCOSE (C6H12O6) OR SUGAR
OXYGEN (O2)

73. Check Yourself!
3. Where does photosynthesis occur in eukaryotic cells?
CHLOROPLAST

74. Check Yourself! 4. Where is the energy in ATP stored?
IN THE BONDS CONNECTING THE PHOSPHATES

75. Check Yourself!
5. Why does the cell use ATP instead of sugar for energy?
ATP IS FASTER AND SMALLER TO USE

76. Check Yourself!
6. What reactants are required for cellular respiration to occur?
GLUCOSE (C6H12O6) OR SUGAR
OXYGEN (O2)

77. Check Yourself! 7. What does cellular respiration produce?
CARBON DIOXIDE (CO2)
WATER (H2O)
ATP (ENERGY)

78. Check Yourself!
8. Where does cellular respiration occur in eukaryotic cells?
MITOCHONDRIA

79. Check Yourself!
How is fermentation alike and different from aerobic respiration?
ALIKE - USES GLUCOSE AS A REACTANT
PRODUCES ATP (ENERGY)
DIFFERENT - AEROBIC USES OXYGEN
FERMENTATION DOES NOT
AEROBIC PRODUCES LOTS OF ATP
FERMENTATION PRODUCES ONLY 2
ATP

80. Comparing Photosynthesis & Respiration
Cellular Respiration
Function
Energy Storage
Energy Release
Location
Chloroplasts
Mitochondria
Reactants
CO2 and H2O and sun
C6H12O6 and O2
Products
CO2 and H2O and energy
Equation
6CO2 + 6H2O +sun  C6H12O6 + 6O2
C6H12O6 + 6O2
6CO2 + 6H2O + energy

81. Cell Energy Processes include:
Photosynthesis
and
Cellular Respiration
Photosynthesis is a STERNGRR process
Cellular Respiration is a STERNGRR process
The two processes work together in a cycle!

82. Photosynthesis
Involves making FOOD (sugar/glucose) for nutrition
CO2 + H2O + sun  C6H12O6 + O2
REACTANTS PRODUCTS
Occurs in the CHLOROPLASTS of plant cells.
Uses the green pigment CHLOROPHYLL to capture light energy
Green light is reflected… all other wavelengths of light are absorbed by the plant.

83. Photosynthesis
What is going in and coming out of the plant?

84. They are 2 different things!
ATP
The food made in photosynthesis is used to make energy for cells!
Food is NOT energy!
They are 2 different things!
Organisms (including plants) must use this food to produce energy
Plants make food for all living organisms (sugar)
ATP is the energy molecule for cells
Adenosine P P P
Energy is stored in a chemical bond – when the bond is broken, energy is released!
Energy

85. Cellular Respiration
Involves using food made in photosynthesis for respiration, to make ATP for energy.
C6H12O6 + O  CO2 + H2O + ATP
REACTANTS PRODUCTS
Occurs in the Mitochondria of ALL cells

86. Cellular respiration can take place
WITH Or
WITHOUT
Oxygen!
Anaerobic respiration (fermentation) takes place when oxygen is NOT present
Aerobic respiration occurs when oxygen is present
Makes a LOT of ATP
Makes a little ATP
In plants and microorganisms:
Alcoholic fermentation
In animals:
Lactic acid fermentation