M5 CH18 respiration Flashcards
(22 cards)
what reaction takes place alongside the conversion of glucose into hexose bisphosphate
the breakdown of 2 ATP molecules
explain how the reactions taking place when triose phosphate becomes pyruvate can be described as redox reactions
triose phosphate is oxidised into pyruvate
NAH is reduced –> NADH
In the link reaction, why does the number of carbons reduce from 3 to 2 when pyruvate is converted into acetate?
it is lost as carbon dioxide
state the net productions of ATP, NADH and pyruvate in glycolysis one glucose molecule.
ATP: 2
NADH: 2
Pyruvate: 2
what does acetate combine with to form the final product of the link reaction?
coenzyme A
how is citrate (6c) formed in the krebs cycle (remember it functions in a circle)
acetyl (2C) from link reaction combines with oxaloacetate (4C) to form citrate.
how many molecules of carbon are lost from one turn of the krebs cycle, and how are they lost.
2
lost as carbon dioxide
how many NADH molecules are formed from one krebs cycle.
- how many are formed from one molecule of glucose.
3
6
why is it incorrect to say that only 1 FADH2 molecule is formed from krebs cycle of one molecule of glucose?
because for one molecule of glucose, kreb cycle occurs twice
therefore, 2 molecules of FADH2 are formed from one molecule of glucose in respiration
how many carbon molecules are lost from krebs cycle (one molecule of glucose)
4
(2 from each turn of krebs cycle)
there are 4 molecules of ATP formed during glycolysis, why is it incorrect to say that the net production of ATP from glycolysis is 4?
because 2 ATP molecules are broken down to provide glucose with 2 phosphates to form hexose bisphosphate.
therefore NET ATP production is only 2
state the reaction that takes place in the electron transport chain
oxidative phosphorylation
explain what happens in the electron transport chain in aerobic respiration
as electrons move down the etc, protons are pumped across the mitochondrial membrane
- changing the shape of ATP synthase, so that it can catalyse the formation of ATP molecules by combining each ADP molecule with an inorganic phosphate.
what is the NET production of ATP in the electron transport chain (oxidative phosphorylation) from one molecule of glucose
34
what is the final electron accepter in the electron transport chain
oxygen
what unnecessary molecule is formed at the end of the etc
water
state the 4 molecules formed in krebs cycle, and the net production of each from one molecule of glucose.
ATP: 2
FADH2: 2
NADH: 6
CO2: 4
(divide each by 2 to find net from only one kreb cycle)
draw a diagram showing the steps involved in lactate fermentation
(enzymes/ reduction & oxidation)
mark using blue bio workbook
draw a diagram showing the steps involved in alcoholic fermentation after glycolysis
mark using blue bio workbook
is lactate fermentation reversible/irreversible ?
why?
is alcoholic fermentation reversible/irreversible?
why?
lactate: reversible
because no molecules are lost as waste products
alcoholic: irreversible
because a carbon molecule is lost from pyruvate (decarboxylation) as a carbon dioxide molecule
outline the process that takes place to use lipids instead of glucose in respiration
- ester bonds between glycerol and F.As are hydrolysed, breaking triglyceride apart
- glycerol enters glycolysis where is is converted to pyruvate
- each fatty acid is broken down into 2 carbon units, forming 6x coenzyme A’s
- enters L.R and krebs cycle
outline the process that takes place to use proteins instead of glucose in respiration
- proteins are hydrolysed into amino acids
- amino acids are deaminated
- carbon part of the deaminated amino acids are converted into pyruvate
- pyruvate enters the link reaction
