Cellular respiration and photosynthesis Flashcards
Main points of aerobic cell respiration
- Glycolysis - 2 NADH, 2 Pyruvate
- Link reaction (oxidative decarboxylation) - Pyruvate —> 2 Acetyl CoA
- The Krebs cycle - 2 CO2
- Oxidative phosphorylation - electron transport chain, chemiosmosis - H2O
Main points of anaerobic cell respiration
- Glycolysis
- Fermentation - lactic acid + 2NAD+ / ethanol + CO2 + 2NAD+
Where does glycolysis take place?
Cytoplasm
Where does the link reaction take place?
Pyruvate passes to the mitochondrial matrix
ATP characteristics:
Adenosine Triphosphate
- can be regenerated (by cell respiration, photosynthesis)
- soluble
- bond between 2 and 3 phosphate group releases energy when broken
ADP
Adenosine Diphosphate
Difference in molecules that aer vs ana can decompose
carbohydrates, lipids, amino acids vs just carbohydrates
Oxygen debt
the amount of oxygen that must be absorbed following anaerobic respiration
Lactic acid production is ceased (tired)
the pH in the blood would be too high
What affects the rate of cell respiration?
- Concentration of Oxygen / Hydrogen
- Temperature
- Glucose levels (respiratory substrate)
- CO2 concentration
Where are photosystem located?
Chloroplast (Eukaryotic) / cell membrane (Prokaryotic) —> Thylakoid membranes
PS II —> PS I
electrons from photolysis, ATP —> e from PS II, NADPH
Photolysis
splitting of water (replaces electrons) using energy from light, O2 byproduct
Chemiosmosis in photosynthesis
pass down the electron transport chain, powers proton pumps, pump protons into the Thylakoid space, p passively diffuse through ATP synthase
RuBisCO
Enzyme responsible for carbon fixation, attachment of CO2 to RuBP (Ribulose Biphosphosphate)
G3P + NADPH + ATP —> TP + NADP + ADP
Glycerate 3 Phosphate —> Triose Phosphate
2 TP —>
6 C glucose / with additional minerals amino acids or lipids
Light dependent reaction
Photosystem II (Photolysis 4H+ + 4e + O2) —> Photosystem I (2e —reductase-> 2NADPH), ATP synthase
Light independent reaction
Calvin cycle, in the Stroma
Proton gradient
Difference in p concentration across a membrane
Carbon fixation
Convergence of inorganic C compounds (CO2) to organic molecules, done by living organism
Membrane proteins - functions
- electron carriers
- active transport - proton gradient
- cell recognition
- enable facilitated diffusion
Oxidative decarboxylation of pyruvate
NAD+ is reduced CO2 produced
Link reaction
2 Pyruvate —> oxidative decarboxylation —> Acetate (+CoA) —> 2 Acetyl Coenzyme A + 2CO2
Glycolysis
Phosphorylation - 2 PO3 added to destabilise glucose
Lysis - Hexose Biphosphate is split to form 2 Triose phosphates
Oxidation - 2 3-C are dephosphorylated to form 2 pyruvate
Calvin cycle
Carbon fixation —> reduction —> regeneration of RuBP
