Lec. 11 Cellular Respiration Flashcards
Cellular respiration refers to _____ _______ (exergonic and energy releasing reactions) to generate ATP
catabolic reactions
Energy comes as ____ energy and leaves as ____ energy
Light, Heat
Defects in mitochondria can result in:
(Good knowledge)
degenerative diseases, cancer, aging
- muscle weakness
-neurodegeneration
- metabolic dysfunction
Transfer of electrons in ____ is central to cellular respiration
redox reactions
Redox:
Glucose is ____
Oxygen is _____
Oxidation: loss of electrons
Reduction: Gain of electrons
Glucose is oxidized since its electrons and H+ is removed to form CO2
Oxygen is reduced because electrons and H+ is added in H20
NAD+ + ___ + ___ = NADH
What is NADH?
H+, 2e-
NADH moves e- to transport chain
3 Stages of Cellular Respiration
- Glycolysis
- Pyruvate oxidation (and Citric Acid Cycle)
- Oxidative phosphorylation (Electron transport and chemiosmosis)
1st stage:
Location, what goes in and comes out
Glycolysis
- Glucose to pyruvate
- In the cytosol
- provides substrates for citric acid cycle (pyruvate) and oxidative phosphorylation (NADH)
- ATP produced through substrate level phosphorylation (ADP comes from substrate rather than Pi)
Net gains/losses of glycolysis
Glucose —-> 2 Pyruvate + 2H2O
2 NAD+ +4e- +4H —> 2NADH + 2H+
2 ATP formed
What happens before the 2nd stage (Intermediate stage)
The pyruvate moves into mitochondrial matrix and the pyruvate is converted to Acetyl CoA
2nd stage:
Location, what goes in and comes out
Citric Acid Cycle
- Mitochondrial matrix
1 Acetyl CoA:
- 2 CO2
3 NADH
1 FADH2
1 ATP
Electron carriers are now loaded
3rd Stage:
Location, what goes in and comes out
Oxidative Phosphorylation
- Inner mitochondria membrane
- NADH and FADH2 donate e-
- proton pumps send H+ to intermembrane space (high H+ concentration)
