BRAINCAKECellular Respiration
Revision notes for Cellular Respiration in Edexcel Biology B (9BI0). Every lesson in BrainCake comes with R.E.C.I.P.E. recall steps, a quick check and spaced reviews.
- Cellular RespirationCellular respiration is the set of enzyme-controlled reactions in which energy is released from a respiratory substrate, such as glucose, and used…
- ATPATP (adenosine triphosphate) is the immediate source of energy for reactions in cells.
- Aerobic RespirationAerobic respiration is respiration that uses oxygen.
- Respiration in the CytoplasmThe first stage of respiration, glycolysis, happens in the cytoplasm of the cell, outside the mitochondria.
- MitochondriaMitochondria are the organelles where the link reaction, the Krebs cycle and oxidative phosphorylation take place.
- Hydrogen AcceptorsMany steps in respiration are oxidation reactions in which hydrogen atoms are removed from a substrate.
- Investigating the Rate of RespirationThe rate of aerobic respiration can be measured with a respirometer, which measures the rate of oxygen uptake by small organisms such as woodlice…
- Investigating the Site of ATP SynthesisHow do we know which parts of the cell carry out each stage of respiration?
- GlycolysisGlycolysis (sugar splitting) is the first stage of both aerobic and anaerobic respiration.
- Anaerobic Respiration in MammalsWhen oxygen is in short supply, as in muscles during vigorous exercise, the electron transport chain stops because there is no final electron…
- LactateLactate produced during anaerobic respiration does not stay in the muscle.
- Sprint AthletesA 100 m sprinter needs a huge amount of ATP very quickly, far faster than oxygen can be delivered to the muscles.
- Anaerobic Respiration in Plants and FungiPlants and fungi such as yeast can also respire without oxygen, for example yeast in a sealed fermenter or plant roots in waterlogged soil.
- Discovery of GlycolysisFor much of the 19th century, scientists argued about how fermentation happens.
- Aerobic Respiration: SummaryHaving studied each stage, we can now follow a glucose molecule all the way through aerobic respiration.
- The Link ReactionWhen oxygen is available, the pyruvate from glycolysis is actively transported into the mitochondrial matrix, where the link reaction takes place.
- The Krebs CycleThe Krebs cycle takes place in the mitochondrial matrix.
- The Electron Transport ChainThe electron transport chain is the final stage of aerobic respiration.
- ChemiosmosisChemiosmosis is the process that uses the proton gradient built up by the electron transport chain to make ATP.
- Net Gain of ATPAdding up the products of each stage shows how much ATP aerobic respiration can make from one glucose molecule.
On the specification
- 5.1 Aerobic respiration
- 5.2 Glycolysis
- 5.3 Link reaction and Krebs cycle
- 5.4 Oxidative phosphorylation
- 5.5 Anaerobic respiration