Where does Glycolysis take place? Does it require O2?
In the cytosol. O2 need not be available because glycolysis is the first step of both aerobic and anaerobic respiration.
How is ATP formed in glycolysis, the kreb's cycle, and the electron transport chain?
Substrate-level phosphorylation in glycolysis and TCA but oxidative-phosphorylation in ETC.
What happens if one enzyme in the glycolytic pathway is inhibited?
Buildup of reactants and reduction of products
Fermentation - what are the net products and what kinds of cells employ it?
Anaerobic respiration taken up my muscle and bacterial cells.
Net products carry over from glycolysis
1. 2 ATP
2. Ethanol of lactic acid from conversion of puryvate
3. NAD+ recovered from glycolysis to reenter cycle
Net ATP produced from aerobic respiration, including glycolysis
Where does TCA take place?
In the mitochondrial matrix
What are the products from one turn of the TCA?
1 ATP ; 3NADH ; 1FADH2 ; oxaloacetate
Inner mitochondrial matrix vs. Outer mitochondrial matrix
Outer = permeable to small molecules
Inner = less permeable than the outer membrane
What other macromolecules can enter the TCA?
Amino acids & triglycerides
Energy yield of NADH and FADH2 in ETC
NADH = 2-3 ATPs
FADH2 = 2 ATPs
Where is the ETC?
In the inner mitochondrial membrane - carries out the oxidation of NADH and FADH2
What is the terminal electron acceptor in the ETC and what is the net product?
Oxygen - this is why O2 is needed for aerobic respiration. By accepting the electrons, oxygen is reduced to water.
What establishes the proton gradient in the intermembrane space?
The oxidation of NADH, which allows protons to be pumped into the intermembrane space
What is the name of the membrane-bound protein responsible for ATP production?
Types of transport not requiring energy
**No energy required because molecules are being moved along their gradient
1. Facilitated diffusion (glucose) ; assiatance of transport proteins needed
2. Passive diffusion
Membrane transport requiring energy
**Need ATP because molecules are moved against their gradient
Active transport (secondary and primary)
What molecular factors affect membrane permeability?
Molecule size and polarity!
Water is more permeable than Na+ even though it's bigger because it is uncharged.
Do enzymes change the free energy of a reaction?
Nope! They also only affect the kinetics of the reaction...not the thermodynamics
In aerobic metabolism, what happens to the C in glucose, the O in glucose, and the inspired O?
C in glucose --> CO2
O in glucose --> CO2
O breathed in --> H2)
What are glycolysis and TCA inhibited by?
ATP! and Krebs by NADH
Net reaction of aerobic respiration and source of products
C6H12O6 + O2 --> CO2 + H2O (unbalanced).
Each half of a glucose molecule forms 18 ATP to give a net of 36ATP per glucose
What are the net products of glycolysis?
What is the net reaction of glycolysis?
2ADP + 2Pi + 2NAD+
--> 2Pyruvate + 2ATP + 2NADH
No O2 should be present because remember that glycolysis is independent of O2