Lecture 28 Flashcards
What does photosynthesis produce
Produces an efficient energy source
In high energy sources like gas and glucose. There are many chemical bonds per molecule. That when broken and reformed into smaller molecules form a higher number of chemical bonds creating energy
What is energy required for and released from
Required for bonds to break
Released when bonds form
Cellular respiration definition
Process by which cells generate the energy storing molecule ATP through a series of redox reactions
Redox rxn in cellular respiration
Electrons removed from carbohydrates such as glucose and are moved to an electron receptor
When this final receptor is oxygen the process is aerobic respiration
When this final receptor is an inorganic molecules. The process is called anaerobic reapiration
When the final receptor is an organic molecule the process is called fermentation
aerobic respiration is when receptor is what
Oxygen
Anaerobic respiration when final receptor is what
Anaerobic molecule
Fermentation is when the final electron receptor is what
An organic molecule
Aerobic cellular respiration formula
C6H12O6 + 6O2 -> 6CO2 + 6H2O + energy
Which oxidizes in aerobic cellular respiration and which reduces
C6H12O6 oxidizes into 6CO2
(Lose electron oxidize)(energy produced)
6O2 reduces into 6H2O
(Gain electron reduce)(energy used)
How do we get energy from gasoline
We INVEST some energy in the form of fire to break down the long hydrocarbons so they can reform into smaller molecules form molecules
How do we get energy from glucose
Invest some energy in the form of glycolysis to break down the long hydrocarbons so they can reform into smaller molecules.
Stages of cellular respiration loosely
Glycolysis
Pyruvate oxidation
Citric acid cycle
Oxidative phosphorylation
Glycolysis loosely
Break down glucose into pyruvate
Pyruvate oxidation
Break down Pyruvate into acetyl-CoA
Citric acid cycle loosely
Break down into NADH/FADH
Oxidative phosphorylation
Break down to water and CO2
Where does cellular respiration happen in eukaryotes
Mitochondria
Glycolysis
Multi step breakdown of one 6-carbon glucose into 2 3-carbon pyruvate with an extra 2 water molecules
Ancient process
Starts with energy investment (have to break bonds first. Like lighting the match for gasoline). Get a (somewhat small) payoff at the end
Where does glycolysis take place
Cytosol
Ingredients of glycolysis
Glucose. ADP + P sub(i), NAD+, ATP, and enzymes
What does glycolysis produce
2 Pyruvate, 2 ATP, 2 NADH
What is ADP/ATP
Adenosine di/tri phosphate
Main chemical energy source for cells. The third phosphate is a very active molecule
NADH
An “electron transporter/ energy carrier”
NAD+ reduced to NADH
NADH oxidized to NAD+
NAD+ + H+ +2e- = NADH
Where does Pyruvate oxidation occur
Mitochondria
What is Pyruvate
3 carbons
CH3-CO-COO^-
How many carbons in Pyruvate
3
Pyruvate oxidation
Pyruvate is oxidized into and acetyl group(note this has 2 carbons), with a coenzyme A which has lots of energy
Basically Pyruvate -> Acetyl- CoA
Has 3 C-H bonds that are broken down in the citric cycle
Krebs cycle AKA
Citric cycle
Where does the citric cycle occur
Matrix of the mitochondria
Citric cycle steps
Four-carbon molecule oxaloacetate accepts two-carbon acetyl group from acetyl-CoA
First product is citric acid
Includes 8 steps each of which is catalyzed by a specific enzyme
Cycle completely disassembles acetyl-CoA, stripping away its electron producing CO2
At the end of each cycle, oxaloacetate has been regenerated (forming a cycle)
Each cycle produces 2 ATP, 6NADH, and 2 FADH2 per glucose molecule
NADH and FADH2 molecules carry most of the energy (in form of high energy electrons) of the original glucose molecule to the next step: electron transport chain
