Lecture 12: Cellular Respiration and Glycolysis Flashcards
is the breakdown of organic molecules exergonic or endergonic?
exergonic
does oxygen need to be present for glycolysis and fermentation?
no, they’re anaerobic processes
can cellular respiration occur without the presence of oxygen?
yes, there’s aerobic and anaerobic cellular respiration
What does anaerobic respiration consume other than O2?
Iron and Sulfate are some examples
what is the equation for cellular respiration?
C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + ATP + heat
During cellular respiration what gets oxidized and what gets reduced?
glucose gets oxidized to CO2 and O2 gets reduced to H2O
what enzyme removes electrons from glucose and transfers them to NAD+ ?
dehydrogenase (NAD+ —> NADH)
what does glycolysis do?
breaks down glucose into two molecules of pyruvate
Where does glycolysis take place?
cytosol
where do pyruvate oxidation and citric acid cycle occur?
mitochondrial matrix
Where does oxidative phosphorylation (ETC & Chemiosmosis) occur?
inner mitochondrial membrane
What is substrate level phosphorylation?
The enzyme-catalyzed formation of ATP by direct transfer of a phosphate group to ADP from an intermediate substrate in catabolism.
what are the two major phases of glycolysis?
- energy investment phase
- energy payoff phase
what are the reactants/products of glycolysis? What is the main goal of this process?
Reactants: glucose, ADP, NAD+
Products: 2 ATP, 2 NADH, 2 pyruvate
Main Goal: to make pyruvate
what does pyruvate need to be converted to before the citric acid cycle can begin?
acetyl CoA
What are the reactants/products in the oxidation of pyruvate?
Reactants: pyruvate, coenzyme A, NAD+
Products: 2 NADH, 2Acetyl CoA, CO2
What are the reactants/products in the citric acid cycle?
Reactants: Acetyl CoA, ADP, FAD+, NAD+,
Products: 2 ATP, 6 NADH, 2 FADH2, 6CO2
Where is most of the chemical energy stored in after glycolysis and citric acid cycle?
10 NADH molecules
How does citrate form in the citric acid cycle?
acetyl joins to oxaloacetate
What are the two electron carriers in cellular respiration?
NADH & FADH2
what is the ETC (electron transport chain) made up of?
protein complexes
Where are electrons going to/from?
going from NADH or FADH2 to ETC
Cytochromes
An iron-containing protein that is a component of electron transport chains in the mitochondria and chloroplasts of eukaryotic cells and the plasma membranes of prokaryotic cells
How is ATP made if the ETC generates no actual ATP?
It breaks the large free-energy drop from food to O2 into smaller steps that release energy in manageable amounts
