Respiration Flashcards
What is ATP?
Adenosine Triphosphate
- universal energy currency which can be hydrolysed to form ADP + Pi to release manageable amounts of energy
How is ATP made?
- Substrate level phosphorylation (glycolysis + krebs cycle)
- Oxidative Phosphorylation (ETC)
What are the 4 steps of Respiration?
- Glycolysis
- Link Reaction
- Krebs Cycle
- OxPhos (ETC)
What is the role of oxygen in aerobic respiration?
Final electron acceptor - if oxygen is not present, whole system collapses
Where does Glycolysis occur?
cytoplasm
What are the 3 stages of glycolysis?
- Phosphorylation - Glucose phosphorylated to form hexose bisphosphate (6C) forms 2 ADP
- Splitting - hexbis forms 2TP
- Oxidation - 4ATP made ,2 NADH made from 2 NAD (done via dehydrogenase enzymes)
forms 2xPYRUVATE
(technically 4ATP made from the 2TP but since 2 were put in at the start that means there is only a net gain of 2ATP)
Where does link reaction occur?
mitochondrial matrix
What are the products of link reaction?
- 1 NADH
- 1 CO2
- Acetyl Coenzyme A
(Acetyl CoA)
(Pyruvate dehydrogenase is the enzyme responsible for decarboxylating and then dehydrogenating the pyruvate so it becomes an acetyl group)
(despite the acetyl coA complex being formed, only acetyl enters the krebs cycle
Where does Krebs Cycle occur?
mitochondrial matrix
What are the products of the Krebs Cycle (1 turn)
- 1 ATP
- 3 NADH
- 1 red. FAD
- 2 CO2
What occurs during OxPhos?
- H+ ion are pumped into intermembrane space via electron transport chain
- Create an H+ gradient for chemiosmosis to occur
- H+ ions move via a channel protein to an ATP synthase molecule where ADP and Pi are condensed to form ATP
Whats the difference between aerobic and anaerobic respiration?
- Aerobic = presence of oxygen, includes link, krebs and OxPhos
- Anaerobic = no presence of oxygen, doesn’t include link, krebs, and OxPhos
GLYCOLYSIS for both though
What is the product of anaerobic respiration in animals ?
lactate
What is the product of anaerobic respiration in fungi / plants?
ethanol
What is the progression of molecules being formed in the krebs cycle?
acetyl group (2C) - (add oxaloacetate (4C) ) citrate (6C) - (loses CO2 + form NADH) 5C compound - (loses CO2 + forms NADH) 4C compound - form ATP (ADP + Pi) 4C compound - (form red. FAD) 4C compound - form NADH oxaloacetate (4C)
6C compound for 1 step
5C compound for 1 step
4C compound for 3 steps