Chapter 9
Cellular Respiration
— Objectives
— Equation for Cellular Respiration
— Electron Carriers and Redox Reactions
— Process of Cell Respiration — Glycolysis — Prep Reaction — Krebs Cycle (Citric Acid Cycle) — Electron Transport Chain
— Fermentation
— The Ingredients
— You already know what is needed for Cellular Respiration
Food + Oxygen Carbon Dioxide+ Water +ENERGY!
C6H12O6 + O2 CO2 +H2O + ATP
— Redox Reactions (the shuffling of electrons)
• Most of the reactions involved in the process are possible because of the redox reaction of NAD, an electron carrier
• Oxidation – a reaction in which a substance loses electrons C6H1206 CO2
• Reduction – a reaction in which a substance gains electrons O2 H2O
• Oxidation always occurs with reduction = Redox Reaction
— NAD: An Electron Carrier
— NAD+ gains an electron to become NAD
— NAD gains a hydrogen to become NADH
— This can also occur with the electron carrier FAD
— Cellular Respiration
— The means in which the cell produces energy
— Often consists of 4 Steps: — Glycolysis — Prep Reaction — Krebs Cycle (Citric Acid Cycle) — Electron Transport Chain
— Glycolysis
• Occurs in the cytosol
• Begins with a molecule of glucose (a 6 carbon sugar)
• Uses the energy of 2 ATP to split the stable glucose into 2 unstable molecules each containing 3 carbons
• Now all processes occur twice
• Phosphates are added and removed to produce 2 molecules of pyruvic acid
— The Prep Reaction
— Occurs inside the mitochondria
— Pyruvic acid reacts with coenzyme A to form acetyl coA and CO2
— NADH is also formed
— Krebs Cycle
• Occurs in the outer compartment of the mitochondria
• Also known as the Citric Acid Cycle
• Acetyl coA reacts with oxaloacetic acid to form citric acid
• Oxidation occurs several times giving off CO2 and 2ATP
• Oxaloacetic acid is regenerated
— A Tally of ATP
— So far, 2 ATP molecules were used in Glycolysis to split glucose.
— 4 ATP molecules were produced in Glycolysis
— 2 ATP molecules were produced in the Krebs Cycle
— Therefore the net yield is 4 ATP molecules
— A Look Back At the Equation:
— C6H12O6 + O2 CO2 +H2O + ATP
— A Look Back At the Equation:
— C6H12O6 + O2 CO2 +H2O + ATP
So far, we have used glucose and produced carbon dioxide and a little ATP
How does the oxygen and water fit in to this?
— Electron Transport Chain
— Occurs in the inner membrane of the mitochondria
— This is the reason for the many folds of the mitochondrial matrix
— Increase surface area allows for more respiration
— Electron Transport Chain
(the shuffling of electrons)
— The electrons from glycolysis and Krebs come to the ETC.
— The proteins embedded in the membrane are specific enzymes that allow NADH and FADH to donate their electrons (e-)
— Electron move to inside of the membrane but protons (H+) get pumped to the outside
— Electron Transport Chain
— Once the concentration gradient is great, the enzyme, ATP synthase allows H+ back inside.
— Phosphates are added to ADP molecules to make 34 ATP
— Oxygen accepts the H+ to produce H2O
— Electron Transport Chain
— Electron Transport Chain Animation
— http://vcell.ndsu.edu/animations/etc/movie.htm
— The process of cellular respiration in the presence of oxygen results in the production of 36 ATP molecules and is known as aerobic respiration
Cellular respiration occurring when oxygen is not present is known as anaerobic respiration or fermentation
— Fermentation
— Occurs when there is no oxygen present
— Only glycolysis occurs
— Alcoholic Fermentation: fungus (yeast) pyruvic acid converts to acetaldehyde to produce ethanol
— Beer and wine (alcohol) is merely the waste product of yeast
— CO2 is given off and used in baking
— Fermentation
— Lactic Acid Fermentation: Animals such as bacteria
— Pyruvic acid is converted to lactic acid
— Yogurt is made this way
— Our muscles burning during exercise is an example
— A Song To Help You Remember:
— http://www.youtube.com/watch?v=wqqYIgY40OE&feature=related
— This is a remake of the Red Hot Chili Peppers "Californication" It is intended to teach the process of Cellular Respiration
Lyrics:

It all starts in your stomach
With that awful, deep sensation
You fill your mouth with food
That comes from Photo-syn-thi-zation
And as you chew amylase eats through
It's straight up mastication

And the enzymes start to break down food
Catabolic transformation
The glucose travels through
Your blood, its active transportation
It moves across cell membranes, now
To Cellular Respiration

It all starts with glycolysis
Anaerobically ensuing
A molecule of glucose used
2 pryuvates it's producing

But is that all?
No that's not all!
2 Molecules of ATP(e)
2 Molecules of NADH

Pryuvates move to the mitochondria
And go through some conversions
They transform to acetyl CoA
And that's the alteration
We get out one NADH
Now on to a rotation

The Krebs cycle goes round and round
Every turn yields one Tri-Phosphate
We also get one FADH2
Which is used in the final formation
With 3 NADHs Now
Electron Translocation

That's the end of the current phase
The next has oxidation
Now let's move to the final stage
Of Cellular Respiration

Just get a clue
As we move to
Oxidative Phosphorylation
Oxidative Phosphorylation
Oxidative Phosphorylation
Oxidative Phosphorylation

FADH2 is the silver in the cell
NADH is the gold
FADH2 becomes 2 ATP
When everything unfolds
NADH becomes 3 ATP
Now come forth and behold

ADP becomes ATP
When everything is converted
The terminal bond it is the key
When a phosphate is inserted

The dews of heaven distilled upon you
Food from Photo-syn-thi-zation
Glycolysis and Transformation
Oxidative Phosphorylation
And that's the end of Respiration
—
— You should be able to…
— Write the equation for cellular respiration
— Define “redox” reaction
— List the 4 Steps to Cellular Respiration
— Tell where each of the steps above occur in the cell and give the products and reactants of each step
— Give the number of ATP molecules generated for each step
— Compare and contrast aerobic respiration with anaerobic respiration

Chapter 10
• Photosynthesis
• Objectives
• Autotrophs vs. Heterotrophs
• The Structure of a Chloroplast
• The Process of Photosynthesis – Light Reaction – Calvin Cycle
• Exceptions – C4 – CAM – Hydrothermal vents
• Photosynthesis
• The process by which certain groups of organisms (autotrophs) capture energy from the sun and convert this solar energy into chemical energy that is initially stored in a carbohydrate
• Photosynthesis: Where?
• A chloroplast is found in the mesophyll cells of a leaf
• The fluid inside the chloroplast is stroma
• Thylakoids are the membranous stacks inside a chloroplast.
• Stomata are the pore like openings on a leaf
• There are approximately 500,000 chloroplasts per leaf
• Why is a plant green? ?
• Why is a plant green?
• Chlorophyll a and b absorbs violets, reds and blues from visible light and reflect green.
• Other pigments are present such as carotenoids that are accessory pigments and become visible in the fall when chlorophyll is broken down.
• Equation for Photosynthesis
• Just like cellular respiration, photosynthesis is represented with an equation that you already know:
• PHOTO :synthesis
• 2 Components of Photosynthesis
• Photo = Light • Light Dependent Reaction
• Synthesis = “to make” • Calvin Cycle
• Why? • To turn light energy into chemical energy
• The Light Reaction
Figure 10.17 page 197
• The Light Dependent Reaction
• A photosystem is a group of pigment molecules that absorb the light from the sun and turn it into chemical energy in a place called the reaction center
• Chlorophyll a is the main pigment that makes a plant appear green
• After light is absorbed, electrons are excited in the primary electron acceptor through a redox reaction
• The Light Dependent Reaction
• A molecule of water is split: electrons are given off and oxygen is produced. A proton gradient is formed (H+)
• The electrons in a high energy state can do several things when they fall: • Release heat ( why black is hot in the sun) • Release light (bioluminescence) • Release energy* (photosynthesis)
• The Light Dependent Reaction
• Electrons from photosystem II are transported to photosystem I by the electron transport chain
• Photosystem I is receiving sunlight simultaneously
• The electrons from both photosystems use the enzyme ATP synthase and the proton gradient to produce ATP and NADPH
• ATP and NADPH are used in the next step…
• The Equation
• Can you account for some of the components of the equation? H20 + CO2 + energy C6H12O6 + O2
• The Calvin Cycle
• A Light Independent Reaction also known as the C3 Cycle
• Discovered by Melvin Calvin using radioactive isotopes.
• Received the Nobel Prize in 1961
• Used to be known as the Dark Reaction, but that was misleading because it does not require darkness
• The Calvin Cycle
• CO2 (1C)combines with the sugar RuBP (5C) by the help of the enzyme rubisco
• This is unstable so it breaks into 3-PGA (3C) * Reason for C3 Cycle
• ATP and NADPH from the light reaction and 3-PGA form G3P G3P + G3P = glucose Long chains of G3P=starch
• 1 molecule becomes plant material while the other 5 get regenerated back into RuBP
• Fate of G3P
• A Summary
• A graphic summary of photosynthesis:
• But, there is a problem!!!
• Photorespiration
• When its hot, the stomata of plants want to close to avoid water lose
• CO2 get left outside and O2 get trapped inside
The solution: C4 plants
• Plants growing where there is a lot of sunlight and not much moisture or growing close together
• Corn and grasses
• C4 Plants
• CO2 binds with PEP to form 4 carbon oxaloacetic acid which is then transported to the bundle sheath cells to be used in the Calvin Cycle later
• This requires energy, therefore C4 plants are not as efficient as C3 plants
• CAM Plants
• Plants such as cacti, pineapple and jade
• Grow in very arid conditions
• To avoid water lose, these plants have their stomata closed during the day and open them at night.
• During the night CO2 is converted to a 4 carbon molecule
• While the stomata are closed during the day, the Calvin Cycle proceeds

• You should be able to…
• Define autotroph and heterotroph
• Label the Parts of a Chloroplast and give their significance to photosynthesis
• Write the equation for photosynthesis
• Describe the steps involved in the Light Reaction and tell where it takes place
• Describe the steps involved in the Calvin Cycle and tell where it takes place
• List the differences between C4, C3, and CAM plants
• Realize the underwater world in hydrothermal vents

Chapter 8
} Metabolism
} Objectives
} Energy ◦ Laws of Thermodynamics ◦ Types of Reactions ◦ ATP
} Enzymes ◦ Energy of Activation ◦ Enzyme-Substrate Complex ◦ Limitations
} Energy
} Kinetic ◦ Energy of motion
} Potential ◦ Stored energy
} Laws of Thermodynamics ◦ 1st: Law of conservation of energy
Energy cannot be created or destroyed, but energy can be changed from one form to another ◦ 2nd: Law of entropy When energy is changed from one form to another, there is a loss of usable energy. Waste energy goes to increase disorder
} Metabolic Reactions and Energy Transformations
} Metabolism- ◦ Sum of cellular chemical reactions in cell
} Reactions- ◦ Exergonic –Energy is released as a product of the reaction ◦ Endergonic Reactions – Energy is put in for the reaction to occur
} ATP
} Adenosine triphosphate (ATP) ◦ Generated from adenosine diphosphate (ADP) ◦ Composed of adenine and ribose (sugar), and three phosphate groups
} Energy transformation ◦ Energy released by an exergonic reaction captured in ATP (ATP >>> ADP) ◦ ATP is used to drive an endergonic reaction
} Enzymes
} Enzymes ◦ Protein molecules that function as catalysts ◦ Unique and specific to the substrate ◦ Lowers the energy of activation
} Animation
} Factors Affecting Enzyme Activity
} Substrate concentration ◦ Enzyme activity increases with substrate concentration due to more frequent collisions between substrate molecules and the enzyme
} Temperature ◦ Enzyme activity increases with temperature
} pH ◦ Optimized for a specific pH
} Enzyme Cofactors ◦ Coenzymes and vitamins
} Enzyme Inhibition ◦ An inhibitor binds to an enzyme and decreases its activity ◦ Energy Production and Usage is Directly Related to…

Photosynthesis and Cellular Respiration ◦
} You should be able to …
} Define the forms of energy and types of reactions
} State the Laws of Thermodynamics
} Describe what ATP is and how it is used
} Describe how an enzyme lowers the energy of activation
} List the limitations that affect enzymatic speed

Chapter 7
The Plasma Membrane:
Life’s Border
• Objectives
• Composition of cellular membranes
• Fluid Mosaic Model
• Permeability ▫ Diffusion/Osmosis ▫ Transport
• Phospholipid Bilayer
• Fluid Mosaic Model
• Singer and Nicolson in 1972
• A sea of lipids with proteins floating on top of it.
• Icebergs drifting through an ocean
• A fluid, phospholipid bilayer with a mosaic of proteins
• Getting Small Substances
Into The Cell *Activity*
Before knowing much about the cell, use logic to arrange the 10 words into 2 categories
• To your best ability, place these terms into 2 categories
Energy Fast Slow
Diffusion Facilitated Diffusion Passive
No energy Pumps Active
Against Concentration gradient
With concentration gradient
• PASSIVE ACTIVE
• Slow Fast
• No energy Energy
• Concentration Gradient Pumps
• Types: Example: ▫ Diffusion Na K Pump ▫ Facilitated Diffusion
• Passive Transport
• Uses Concentration Gradients to move molecules of HIGH concentration to areas of LOW concentration
• This is a general rule of nature
• Law of Thermodynamics states that molecules will move from their ordered state to their most disordered state
• Passive Transport
• Simple Diffusion ▫ Does not require energy ▫ Small molecules such as oxygen and carbon dioxide ▫ Fat soluble molecules such as steroids ▫ Example: Osmosis – simple diffusion of water across a semipermeable membrane
• Passive Transport: Osmosis
• Hypertonic solution – a fluid that has a higher concentration of solutes than another
• Hypotonic solution – a fluid with a lower concentration of solutes than another
• Isotonic – two solutions having equal concentrations of solutes
• Passive Transport: Osmosis
• Osmotic Imbalance
• Plants experience turgor pressure because of the cell wall
• Animal cells can burst Question: What happens to red blood cells when you drink too much salt water?
• Small fresh water organisms use the contractile vacuole to pump excess water out
• Passive Transport:
Facilitated Diffusion
• Passage of molecules through a semipermeable membrane with the help of a concentration gradient and a transport protein
• Transport proteins are specific for only one type of substance
• Example: Glucose attaches to a glucose transport protein, the protein changes its shape and allows the glucose into the cell
• Active Transport
• Requires energy (ATP)
• Used when the concentration needs to be higher on one side of the membrane
• Use of pumps to move molecules against the concentration gradient
• Example: The Sodium-Potassium Pump:
• Active Transport:
The Sodium-Potassium Pump
• Necessary for nerve cells to have a higher concentration of potassium inside the cell and a high concentration of sodium outside the cell
•
Phagocytosis
• Remember the endomembrane system from previous chapter
• An amoeba extends the cell membrane around a food particle and draws it into the cell.
• The cell membrane pinches off to form a vesicle, once inside lysosomes break down the contents and the cell membrane is regenerated
• The human immune system uses this mechanism on bacteria also
Phagocytosis[->0] in Amoeba[->1]
• Pinocytosis
• The same mechanism as phagocytosis, but used to bring fluids and their nutrients into the cell
• Receptor-Mediated Endocytosis
•
Exocytosis
• This mechanism is the opposite as endocytosis in which a contents inside the cell are enclosed in a vesicle, the vesicle travels to the plasma membrane and fuses, thus releasing its contents to the outside of the cell.
• Proteins and waste are transported in this way
•
• You should be able to…
• Describe the Fluid Mosaic Model
• Know the difference between active and passive transport and examples of each
• Describe the operation of the sodium-potassium pump.
• Explain how larger particles and molecules move across the membrane

[->0] - http://www.youtube.com/watch?v=ojrkxmD6tT8
[->1] - http://www.youtube.com/watch?v=ojrkxmD6tT8