ch 9: cellular respiration Flashcards
glycolysis
oxidation of glucose
what are the inputs of glycolysis?
- glucose
- 2 NAD+
- 2 ATP
- 4 ADP + 4Pi
outputs of glycolysis
- 2 molecules of pyruvate
- 2 NADH
- 4 ATP
what gets reduced in glycolysis?
NAD+ into NADH
what gets oxidized in glycolysis?
glucose becomes 2 molecules of pyruvate
how does the ATP cycle work in glycolysis?
- 2 ATP are used up in the first step of glycolysis and becomes ADP
- the 4 ADP results in 4 ATP in the second step
substrate level phosphorylation
enzyme directly transfers a phosphate group from another substrate to ADP to create ATP
what is glycolysis regulated by?
excess ATP
why does ATP stop glycolysis and how does it do it?
because cells make ATP as needed, so it stops it by binding to the regulatory site and changing the shape of the protein forcing the function to change, which stops glycolysis
where does glycolysis occur?
in the cytosol
can glycolysis occur in all cell types?
yes, because all cells have cytosol
does glycolysis require oxygen?
NO
aerobic respiration of glucose
the products of glycolysis from the cytosol get brought into the mitochondria
does aerobic respiration of glucose occur in all cell types?
no, only eukaryotes because they have a mitochondria
is oxygen required for cellular respiration?
YES
pyruvate oxidation and processing
moving from the cytosol to the mitochondria
where is pyruvate shuttled to from cytosol?
mitochondrial matrix
does pyruvate get oxidized?
yes and it forms acetyl-CoA
inputs of pyruvate processing
2 pyruvate
2 NAD+
coenzyme A
what gets reduced in the pyruvate oxidation step?
NAD+ is reduced into NADH
outputs of pyruvate processing
2 NADH
2 CO2
2 acetyl coa
what is formed in the step of pyruvate oxidation?
first molecule of CO2`
oxidative phosphorylation
production of ATP molecules by ATP synthase using the proton gradient established by redox reactions of the electron transport chain
does substrate-level or oxidative phosphorylation produce more ATP?
oxidative phosphorylation
ATP synthase
the enzyme that creates ATP and releases it
what is the main purpose of the citric acid cycle?
NAD+ and FAD2+ reduced to NADH and FADH2
inputs of citric acid cycle
2 acetyl coa
3 NAD+
1 ADP
1 FAD
outputs of citric acid cycle
2 ATP
6 NADH
2 FADH
4 CO2
how many times does the citric acid happen per 1 glucose?
2 times
is the citric acid cycle anaerobic or aerobic?
aerobic
is the ATP in the citric acid cycle made by substrate-level or oxidative phosphorylation?
substrate-level phosphorylation
what do NADH and FADH do after being reduced?
carry H+ atoms from the citric acid cycle to the electron transport chain
how is the citric acid cycle regulated?
acetyl CoA is stopped by allosteric regulation by ATP and NAD+ reduction is stopped by competitive inhibition by NADH
what is necessary to power the ATP synthase and where does this happen?
high concentration of H+ ions in the intermembrane space which occurs in the electron transport chain
where are the H+ ions coming from in the electron transport chain?
NADH and FADH2
how are the H+ ions activating the ATP synthase?
it uses energy from an electron to carry out active transport of H+ against the concentration gradient
what also happens to the ETC while actively transporting the H+?
the protein complexes and cofactors of the ETC undergo redox reactions
what is the final electron acceptor in the redox chain?
oxygen
what happens to the oxygen in the final step?
combines with H+ to make H2O
what do the pool of H+ ions do after active transport?
activates and spins the ATP synthase which then creates and releases 25 ATP
is cellular respiration exergonic or endergonic?
exergonic
what happens if there is no oxygen available for cellular respiration?
the mitochondiral metabolism is blocked meaning pyruvate cannot be processed
what other process can still occur without oxygen?
fermentation: which oxidizes NADH into NAD+
what happens when there is no glucose?
fats and proteins feed aerobic respiration with the atoms needed to power the ATP synthase
is cellular respiration aerobic or anaerobic?
aerobic
what are the final outputs of cellular respiration?
H2O, Co2, and many ATP
fermentation
anaerobic process and converts pyruvate into lactic acid or ethanol + CO2
