Chapter 4 - Cellular Respiration Flashcards
What is aerobic respiration?
Process that uses oxygen to harvest energy from organic compounds
Process that extracts energy from food in the presence of oxygen
What are Obligate Aerobes?
These are organisms that cannot survive without oxygen
Aerobic cellular respiration can be broken down into how many stages?
4 stages
Each stage of the cellular respiration produces ATP using how many methods? What’re they?
2;
Substrate-level Phosphorylation
Oxidative Phosphorylation
What is substrate level phosphorylation?
ATP that can be directly formed through an enzyme-catalyzed reaction that transfers a phosphate group from a substrate to ADP
What is oxidative phosphorylation?
Forming ATP indirectly through a series of redox reactions involving a final electron acceptor
What is the first stage of cellular respiration?
Glycolysis
Where does Glycolysis occur?
In the cytosol
What occurs during Glycolysis?
Enzymes break down a molecule of glucose into 2 pyruvate molecules. Some ATP and NADH is synthesized as well
What is the second step in cellular respiration?
Pyruvate Oxidation
What occurs during Pyruvate Oxidation?
The 2 pyruvate molecules made in glycolysis are transported to the Mitochondria and they’re oxidized resulting in NADH and Acetyl-coA (coenzyme A), along with CO2 as a waste product
Where does Pyruvate Oxidation occur?
In the Mitochondria
What is the third step in cellular respiration?
Citric Acid Cycle
Where does the Citric Acid Cycle occur?
In the Mitochondria
What happens during the Citric Acid Cycle?
Acetyl-CoA which was made during pyruvate oxidation enter a cycle where the acetyl group is completely oxidized to CO2. ATP and electron carried NADH and FADH2 are synthesized.
What is the last step in cellular respiration?
Electron transport chain
What occurs during the electron transport chain?
The NADH and FADH2 from the Citric Acid Cycle are oxidized. Their high energy electrons are passed from one oxidizing agent to another until they are transferred to O2, producing water. The free energy released during electron transport is indirectly used to synthesize ATP by oxidative phosphorylation
What 3 steps of cellular respiration use substrate level phosphorylation to synthesize ATP?
Glycolysis, pyruvate oxidation, and citric acid cycle
What step used oxidative phosphorylation to synthesize ATP?
Electron transport chain
Describe the structure of the mitochondria?
- Comprised of 2 membranes
- Outer and inner membranes define 2 compartments
- Intermembrane space is between inner and outer membrane
- Matrix is the inner aqueous environment of the organelle
How many processes are there which allow cells to oxidize fuel molecules WITHOUT oxygen? What are they?
2;
- Anaerobic respiration
- Fermentation
What is anaerobic respiration?
Similar to aerobic respiration in using a series of electron transferring steps, but it uses an INORGANIC molecule other than oxygen as the final oxidizing agent
What is Fermentation?
Doesn’t use the electron transport system and instead it relies on an ORGANIC compound as the final oxidizing agent
What are obligate anaerobes?
These are organisms that cannot survive IN the presence of oxygen
