vocab

exergonic reactions - energy released into environment

endergonic reactions - energy required in order for a process to occur

phosphorylation - process of adding a phosphate group to a molecule

respiratory substrate - any molecule that can be oxidised/broken down in cellular respiration to produce ATP/energy

cell respiration - the controlled release of energy from organic compounds in cells

  • is the main process that provides cells with energy

  • 2 types - aerobic & anaerobic

aerobic respiration - type of cellular respiration that occurs in presence of oxygen

  • can use any respiratory substrate

  • high yield of ATP

  • waste products - H2O & CO2

anaerobic respiration - a type of cellular respiration that occurs in absence of oxygen

  • can only use carbs (like glucose) for respiratory substrates

  • low ATP yield (net gain of 2 molecules)

  • waste product - lactate (lactic acid)

NAD (Nicotinamide adenine dinucleotide) - a type of coenzyme that is used in cell respiration

  • it can be oxidised & reduced

coenzyme - a non-protein molecule that helps enzymes carry out their function

reduced - a chemical reaction where a molecule gains electrons (becomes more negative)

oxidation - a chemical reaction where a molecule loses electrons (becomes more positive)

reduction-oxidation (redox) reactions - a class of reactions where electrons are transported between two molecules

  • when one molecules is oxidised, the other molecule is reduced

dehydrogenation - a chemical reaction where a molecule loses their hydrogen

glycolysis - the first step in anaerobic & aerobic respiration, where 1 glucose is broken down into 2 pyruvate in order to produce ATP & occurs in cell’s cytoplasm

lactic acid fermentation - a type of anaerobic respiration

  • pyruvate is converted to lactate

  • this produces ATP & oxidises NADH back to NAD

alcohol fermentation - a type of anaerobic respiration where pyruvate is converted to ethanol & carbon dioxide, producing ATP & NAD

decarboxylation - the removal of a carboxyl group from a molecule, forming a molecule of carbon dioxide

oxidative decarboxylation - process of removing a carboxyl group from a molecule, while also oxidising it so that the electrons are transferred to NAD

FAD (Flavin adenine dinucleotide) - a type of coenzyme that also functions as a hydrogen carrier

  • when reduced, it can carry one more hydrogen ion than NAD

ATP synthase - an enzyme that uses the energy created by the movement of H+ down their concentration gradient, to synthesize ATP

proton motive force - the electrochemical gradient created by the transfer of protons across a membrane, which can be used to power ATP synthase

terminal electron acceptor - the molecule that receives the electrons at the end of the Electron Transport Chain