Respiration Flashcards
What is the net ATP production of aerobic respiration>
Up to 38 molecules of ATP.
What is the net number of molecules formed per molecule of glucose in glycolysis?
A net of 2 molecules of ATP, 2 molecules of pyruvate, and 2 molecules of NADH are produced during the reaction.
What is the net number of molecules formed per molecule of glucose in the Kreb’s cycle?
6 NADH, 2 FADH, 2ATP, and 4CO2.
What stages does glycolysis involve?
The first step in glycolysis is the phosphorylation of glucose to glucose phosphate using one molecule of ATP. Glucose phosphate is then phosphorylated again to fructose diphosphate and then splits into two molecules of triose phosphate. The two molecules of TP are then oxidised to pyruvate. This also forms 4 ATP molecules and 2 NADH.
What happens after glycolysis if respiration is anaerobic or aerobic?
If respiration is only anaerobic, pyruvate can be converted to ethanol or lactate using reduced NAD. The oxidised NAD produced in this way can be used in further glycolysis
If respiration is aerobic, pyruvate from glycolysis enters the mitochondrial matrix by active transport.
What stages does the Link reaction involve?
Each 3 carbon pyruvate is converted into 2 carbon acetate by oxidation (produces reduced NAD) which then combines with co-enzyme A to form Acetyl COA. CO2 is removed in a process called decarboxylation.
What is the first stage of the Kreb’s cycle after the link reaction?
First acetyl COA reacts with a four-carbon molecule, releasing coenzyme A and producing a six-carbon molecule (citric acid) that enters the Krebs cycle.
What is the second stage of the Kreb’s cycle after the link reaction?
Citric acid undergoes decarboxylation to produce a 5C compound which also undergoes decarboxylation to produce a 4C compound. This step also produces sufficient energy to form ATP.
Where do the hydrogen ions move from, to, and leave through ATP synthase?
They move from the inner mitochondrial membrane and into inter-membranal space and then move through facilitated diffusion to the mitochondrial matrix..
What is the energy source for the hydrogen ions actively transporting from the inner mitochondrial membrane into inter-membranal space?
Electrons pass through a chain of electron transfer molecules in a series of redox reactions.
Which molecules donate electrons to the first molecule in the electron transfer chain?
The reduced NAD and FAD donate electrons from the hydrogen atoms they are carrying.
What is the final acceptor of electrons in oxidative phosphorylation?
Oxygen. It binds with electrons and hydrogen ions to form water.
What is the importance of oxygen in aerobic respiration?
It acts as the final electron acceptor and of the hydrogen ions produced in glycolysis and the Kreb’s cycle. Without it the hydrogen ions and electrons would ‘back up’ and respiration will come to a halt.
Describe the respiration of lipids:
Lipids are first hydrolysed and the glycerol is then phosphorylated and converted to triose phosphate which then enters glycolysis. The fatty acids are broken down into 2 carbon compounds which are converted to acetyl COA. This then enters Kreb’s Cycle.
Describe the respiration of proteins:
First, it is hydrolysed to its constituent amino acids. These undergo deamination before entering the respiratory pathway, 3-carbon converted to pyruvate, 4 and 5-carbon converted to intermediates in the Kreb’s Cycle.
