Respiration Flashcards
stages of respiration (4)
1) glycolysis
2) link reaction
3) krebbs cycle
4) electron transport chain
where does glycolysis occur?
cytoplasm
net products of glycolysis
- 2 ATP
- 2 pyruvate
- 2 NADH
where does link reaction occur?
matrix
products of the link reaction
2 acetyl co-enzyme A
2 NADH
2 CO2
where does krebbs cycle occur?
matrix
products of krebbs cycle
- 6 NADH
- 2 FADH
where does electron transport chain occur?
cristae
overall products of first 3 stages
10 x NADH
2 x FADH
anaerobic respiration
when O2 is NOT final electron acceptor
oxygen debt
amount of oxygen required to convert lactic acid to CO2 and H2O
stages of anaerobic respiration in plants and yeast
glucose -> pyruvate —[CO2 produced]–> ethanal –[NAD produced]–> ethanal + CO2
stages of anaerobic respiration in animals
glucose -> pyruvate (reduced) –[ NAD produced]–> lactic acid
co enzyme
molecules which some enzymes require in order to function
role of co enzymes in respiration
carry H atoms from one molecule to another
co enzyme eg. (3)
- NAD
- FAD
- NADP - (photosynthesis)
significance of Krebs cycle (4)
- breaks down big molecules into smaller ones - pyruvate into CO2
- produces H atoms which are carried by co enzymes to electron transport chain - leading to production of ATP which produces metabolic energy for the cell
- regenerates 4C molecule which combines with acetyl coenzyme a which would otherwise accumulate
- source of intermediate compounds used by cells in the manufacture of other important compounds eg. chlorophyll + fatty acids
role of oxygen in respiration
final hydrogen acceptor - removes H atoms at end of the chain so that H+ and e- dont back up the chain
why does anaerobic respiration produce less ATP than aerobic?
relies on substrate level phosphorylation - only 2 atp from glycolysis
many more from Krebs and link and ETC - oxidative phosphorylation
What substance is converted to ethanol under anaerobic conditions in ethanol fermentation?
pyruvate
What enzyme catalyses the reaction in which pyruvate is reduced to lactate?
lactate dehydrogenase
What is the name of the process in which protons diffuse down the concentration gradient through the ATP synthase enzyme, creating ATP in oxidative phosphorylation?
chemiosmosis
What processes are applied to the six-carbon molecule citrate, to convert it to a five-carbon molecule in the Krebs cycle?
- decarboxylation
- dehydrogenation
what makes ATP suitable as a source of energy (3)?
- relatively small amount of energy produced
- can be resynthesises rapidly
- releases energy instantly
