9 Flashcards
What is cellular respiration? What are its properties?
- A three step catabolic pathway that uses oxygen to break down glucose (sugar) to get energy for the cell to use.
What are the 3 steps or cellular respiration? Where do these steps occur?
- Glycolysis (the cytoplasm)
- Citric acid cycle (inside mitochondria)
- Electron transport chain (inside mitochondria
What is fermentation?
- An anaerobic (no oxygen) process
- Only does glycolysis, and therefore produces less energy
What are the 2 types of redox reactions?
- Oxidation
- Reduction
What is oxidation?
Molecule gas electrons stripped from it
What is reduction?
Molecule gains electrons
What are the two reducing and oxidizing agents in cellular respiration?
NAD*H and FAD+H
In cellular respiration, what gets reduced? What gets oxidized?
- Sugar is oxidized to CO2
- O2 is reduced to water
What are the two types of phosphorylation?
- Substrate level phosphorylation
- Oxidative phosphorylation
What is substrate level phosphorylation? What are its properties?where does it occur?
- Happens in glycolysis and the citric acid cycle
- Produces 2 ATP in glycolysis and 2 ATP in the Citric acid cycle
- An enzyme takes a substrate that has an inorganic phosphate attached to it, and attatches an ADP to it, making ATP
How much ATP is produced in glycolysis?
2
How much ATP is produced in the Citric Acid cycle?
2
What’s another name for the citric acid cycle?
The Krebs Cycle
What is oxidative phosphorylation? What are its properties? Where does it occur?
- Happens in the electron transport chain
- Is paired with chemiosmosis (final step of cellular respiration)
- NADH and FADH2 carry electrons to the Electron Transport Chain
2 They go down the chain and are stripped of their electrons. The electrons flow across the mitochondrial membrane and through ATP Synthase.
How much ATP does Oxidative phosphorylation produce?
28-32 in the Electron Transport Chain
What is chemiosmosis?
NADH and FADH2 carry electrons to the Electron Transport Chain
2 They go down the chain and are stripped of their electrons. The electrons flow across the mitochondrial membrane and through ATP Synthase.
What are the steps of glycolysis (using 1 glucose molecule)? What is formed? Is CO2 released?
- Broken down into 2 pyruvate molecules
- NAD+ gets reduced
- 2 NADH* are formed
- 2 ATP form
- NO CO2 IS RELEASED
- Happens in the cytoplasm outside the mitochondria
Steps of Intermediate reaction. What is given off?
- The 2 pyruvate travel to the mitochondria.
- Links glycolysis and the Krebs Cycle
- Pyruvate is changed enzymatically to Acetyl CoA (this is because it can’t enter the citric acid cycle)
- 2 CO2, 2 NADH and 2 Acetyl CoA molecules are formed (1 per pyruvate, but there are 2 pyruvates so 2 of each is the net gain
The Citric Acid Cycle steps. What is produced?
- 2 Acetyl CoA is oxidized and are stripped of all their electrons
- 4 CO2, 2 ATP and 2 FADH2 and 6 NADH are formed (this is per every 2 Acetyl CoA. Just one would be half.)
The Electron Transport Chain and Steps. What is produced?
- NADH and FADH2 are stripped of all electrons
- NAD+ and. FAD+ return to the start to get more electrons
- Electrons flow across the mitochondrial membrane to ATP synthase
- Form 28-34 ATP via oxidative phosphorylation.
- H+ ions join with oxygen and form H2O as a byproduct
Net summary of production and steps:
- Glycolysis: 2 ATP, 2 Pyruvate, 2 NADH
- Intermediate reaction: 2 Acetyl CoA, 2 CO2, 2 NADH
- 6 NADH, 2 FADH2, 4 CO2, 2 ATP
- Electron transport chain: 28-32 ATP, H2O
Is pyruvate formed during fermentation? Why it why not?
No, because no oxygen is present
What are the two types of fermentation?
Lactic and alcoholic
What is produced from lactic acid fermentation?
- 2 ATP
- Lactate acts as the oxidant and reductant
Alcohol fermentation steps and production
- 2 ATP is formed
- NAD+ regeneration happens with ethanol instead of pyruvate. Common in yeast.
