respiration Flashcards
what are the locations for each part of the respiration process
glycolysis = cytoplasm
link reaction = mitochondrial matrix
Krebs cycle = mitochondrial matrix
oxidative phosphorylation = inner mitochondrial membrane
process of glycolysis
.two ATP donate phosphate groups to glucose forming hexose biphosphate
.hexose biphosphate molecule is split into two triose phosphates(TP)
.a second phosphate group is added to each TP molecule turning them into triose biphosphate
.hydrogen is removed from triose biphosphate and is used to form two reduced NADP , two pyruvate and 4 ATP via substrate level phosphorylation
link reaction process
.pyruvate from glycolysis is actively transported into the mitochondrial matrix by carrier proteins
.each pyruvate molecule is decarboxylated losing a CO2
.CO2 is diffused out of the mitochondria as waste product
.two hydrogens are removed from the pyruvate to form acetate
.hydrogen is used to reduce the NADP into reduced NADP(electron carrier)
.acetate binds to CoA forming acetyl CoA
Krebs cycle process
.acetyl CoA merges with oxaloacetate to form citrate
.citrate is decarboxylated releasing two CO2
.citrate is also dehydrogenated releasing hydrogens that reduce 3 NAD and a FAD
.for each acetyl CoA one ATP is synthesised directly via substrate level phosphorylation
.oxaloacetate is regenerated for the next turn
oxidative phosphorylation process
.reduced NAD and FAD release hydrogen transferring protons and electrons into the mitochondrial matrix
.high-energy electrons are passed to an electron carrier from reduced NAD and FAD
.the electrons are passed along a series of electron carrier molecules in the electron transport chain releasing energy as they are transferred
.energy is used to actively transport protons across the inner mitochondria membrane from the matrix into the intermembrane space
.protons diffuse back into mitochondrial matrix down their electrochemical gradient through ATP synthase
.this releases energy and catalyses the synthesis of ATP from ADP an Pi
.oxygen is the final electron acceptor, combines with electrons and proton to form water helping maintain the proton gradient
what is chemiosmosis
the diffusion of protons across a partially permeable inner mitochondrial membrane down the electrochemical gradient via ATP synthase channels
total ATP yield per glucose molecule
.34 net gain
.2 from glycolysis
.2 from Krebs
.30 from oxidative phosphorylation
anaerobic vs aerobic
.aerobic occurs in the cytoplasm and in the mitochondria whereas anaerobic occurs only in the cytoplasm
.aerobic has the link reaction, Krebs cycle and oxidative phosphorylation whereas anaerobic only has glycolysis
.aerobic yields 34 ATP where as anaerobic yields 2 ATP per glucose
what are obligate anaerobes
organisms that cannot survive in the presence of oxygen
what are facultative anaerobes
organisms that switch between aerobic and anaerobic respiration
what are obligate aerobes
organisms that depends of oxygen to synthesise ATP
alcohol fermentation (anaerobic respiration)
.occurs in yeasts and some plants
.pyruvate loses a CO2 and is converted into ethanal
.ethanal accepts a H from reduced NADP forming ethanol and regenerating NADP
.ethanol cannot be metabolised and so it is removed as waste product
lactic acid fermentation
.occurs in animals and bacteria
.pyruvate accepts H from reduced NADP, catalysed by lactate dehydrogenase
.this forms lactic acid and regenerates NADP
.lactic acid can be oxidised back into pyruvate to generate more ATP or is stored as glycogen
what happens if too much anaerobic respiration occurs
.there is a reduced quantity of ATP
.so vital processes cannot be maintained for long periods of time
