Seminar 10: How do organisms generate energy from organic molecules II? Flashcards
what is transamination
- anabolic process of synthesising glucose
- Convert A.A into alpha keto acids & glutamate
what is deamination
- remove NH2 from A.A
- Catabolic
- Preps A.A for energy prod, conversion into fats/glucose, nitrogen excreted as UREA
- Important for A.A breakdown & waste removal
what is beta-oxidation
- breakdown of F.A into Acetyl-CoA units
- Catabolic
- Acetyl-CoA is oxidised (yield shorter F.A which are then reduced to NADH & FADH2, go to ETC)
what is lipogenesis
- synthesis of F.A from non-lipid precursors
- Anabolic
- Converts Acetyl-CoA (from excess glucose or A.A) into F.A which are stored as TRIGLYCERIDES
- Stores energy when nutrients are abundant
what is gluconeogenesis
- synthesis of glucose from non-carbohydrate sources
- Anabolic
- A.A, lactate, glycerol made into glucose (almost reverse of glycolysis)
- Maintain blood sugar lvls during fasting, starvation
how is ATP produced?
- E- move through ETC in the inner mitochondrial matrix
- Causes proton pumps to pump H+ to inter membrane space
- High conc of H+ on opp side - H+ will flow to other side because of diffusion (from high to low conc)
- Flow back INTO matrix via ATP synthase - Causes transmembrane protein complexes to CHANGE shape
- Potential energy > kinetic causes central subunit of ATP synthase to ROTATE
- Rotation causes lower subunit to change shape
- Exposes active site for ATP synthesis (ADP + Pi > ATP)
what is the NADH pathway for ETC
- E- moved through protein complex 1 or 2
- Move e- through Q (mobile - moves in membrane b/w protein complexes)
- Cytochrome C carries e- from complex 1 to 4
- E- accepted by half O2 molecule (forms H2O)
what is the func of the mitochondria membrane in ETC?
Compartmentalises spaces
- separates inter membrane space & mitochondrial matrix (this allows concentration grad to form)
- ETC relies on conc gradient to pump through ATP synthase & form ATP.
where does the ETC occur?
mitochondrial matrix`
what is the func of the proteins embedded w/in the mitochondrial membrane?
Protein complexes WITHIN the inner mitochondrial membrane
- e- pass through these, creates a conc gradient w/ H+, allows ATP synthase to form ATP as ATP synthase moves.
What 2 molecules are central to catabolic pathways of all 3 macromolecules? and WHY
- Acetyl CoA & Pyruvate
- They regulate TCA cycle (pyruvate links glycolysis w/ TCA)
- Oxidation of Acetyl CoA forms ATP, NADH & FADH2 (all req. for all pathways)
what is the eqn for 1 complete turn of TCA cycle?
2 Acetyl CoA > 2 ATP + 2 FADH2 + 8 NADH + 6 CO2
desc the TCA cycle
- 8 reactions which COMPLETELY OXIDISES acetyl grp > 2 molecules of CO2
- energy released is caputured by GDP (similar to ATP), NAD+ & FAD)
- oxaloacetate regenerated in LAST STEP (so cycle can cont)
why is O2 req for TCA?
- To regenerate NAD+ & FAD for e- carriers
- No regeneration = no TCA (anaerobic)
- No reduction/oxidation reaction can occur w/o e- carriers (TCA will stop - regulatory point)
role of O2 for TCA
- O2 reduced to H2O as NADH is oxidised to NAD+ (reduction coupling)
- Allows another molecule of glucose to be metabolized & broken down
