Glucose Catabolism Flashcards
In which two ways can glucose be catabolized?
- Cellular respiration
2. Fermentation
What is the difference between cellular respiration and fermentation?
Cellular respiration:
- Oxygen serves as the final electron acceptor
- Generates ATP mostly be oxidative phosphorylation (use of ETC)
- Most efficient method. 1 glucose produces about 32-38 ATP
Fermentation:
- Organic molecule serves as the final electron acceptor
- ATP is generated by substrate level phosphorylation (free roaming enzyme adds phosphate to ADP to create ATP_
- Less efficient. 1 glucose produces 2 ATP.
- Results in lactic acid side product
If glucose fermentation occurs, what product will also be created?
2 ATP and lactic acid
3 main steps and transition reaction in the glucose cellular respiration pathway
Glycolysis
(transition reaction)
Krebs
ETC
Where and how many reactions occur in the cell during glycolysis?
Where- in the cytoplasm
How many- 10 reactions result in 2 net ATP, 2 NADH, and 2 pyruvate
Glycolysis divided into 2 main phases
- Investment phase 1-5
2. Payoff phase 6-10
How many carbons are in
- Glucose
- pyruvate
- 6
2. 3
Glycolysis in the cytosol- is this substrate level phosphorylation or oxidative?
Substrate level.
What occurs during the transition phase between glycolysis and krebs cycle?
During the transition reaction, the pyruvate is shuttled into the mitochondrial matrix and oxidized to acetyl coA.
During this reaction, NAD+ is rescued to NADH, which produces CO2 and C-C (acetyl coA)
This occurs twice since there are 2 pyruvate!
What are the end products of glycolysis
2 NADH, 2 ATP and 2 Pyruvate
What does the krebs cycle produce
Each molecule of acetyl coA produces 3 NADH, 1 FADH2, 1 GTP (ATP) and 2 Co2
In total (since there are 2 acetyl coA)= 6 NADH, 2 FADH2, 2 GTP (ATP) and 4 Co2
What occurs during krebs cycle
When acetyl coA (a 2 carbon molecule) enters, it binds with oxaloacetate (a 4 carbon molecule) to produce citrate (a 6 carbon molecule).
It is then reduced until oxaloacetate is reformed and results in the production of 2 NADH, 1 FADH2, 1 GTP/ATP (by substrate level phosphorylation) and 2 co2 (X2)
Oxaloacetate and citrate
oxaloacetate (4 carbon) that binds with acetyl coA (2 carbon) to produce citrate (6 carbon)
Where is the ETC located?
Embedded in the inner mitochondrial matrix between the inter membrane space and mitochondrial matrix.
When NADH and FADH2 enter the ETC, which complexes do they pass their electrons to?
NADH gives electrons to complex I
FADH2 gives its electrons to complex II
All based on electronegativity
