Unit 1, Module 4 Glossary Flashcards
ATP
A phosphorylated nucleotide and is the universal energy currency.
Energy
The ability to do work
Anabolic reactions
Biochemical reactions where large molecules are synthesised from smaller ones.
Catabolic reactions
Biochemical reactions where larger molecules are hydrolysed to produce smaller molecules.
Oxidation reactions
Involve the loss of electrons
Reduction reactions
Involve the addition of electrons
NAD
Coenzyme involved in respiration. It removes hydrogen atoms from substrates. It becomes reduced NAD, which carries hydrogen atoms.
Coenzyme A
A coenzyme that carries acetate from the link reaction of respiration to Krebs cycle.
Glycolysis
A metabolic pathway where each glucose molecules is broken down to two molecules of pyruvate. It occurs in the cytoplasm of all living cells and is common to anaerobic and aerobic pathways.
Hexose sugars
Sugars with six carbon atoms in each molecule.
Hydrolysis
The breaking down of large molecules to smaller molecules by the addition of water.
Triose sugars
Sugars which have three carbon atoms in each molecule.
Substrate-level phosphorylation
Formation of ATP from ADP and Pi during glycolysis and the Krebs cycle.
Mitochondria
Organelles found in eukaryote cells. They are the sites of the link reaction, Krebs cycle and oxidative phosphorylation - the aerobic stages of respiration.
Cristae
The folded inner membrane of mitochondria that gives it a large suface area.
Intermembrane space
The area between the inner and outer membranes.
Matrix
The semi-rigid and gel-like mixture of proteins and lipids enclosed by the inner membrane.
Electron carriers
Molecules that transfer electrons
ATP synthase
Enzyme associated with stalked particles in mitochondria and chloroplasts. It catalyses the joining of ADP and inorganic phosphate to make ATP.
Link reaction
Converts pyruvate to acetate. NAD is reduced.
Krebs cycle
Oxidises acetate to carbon dioxide. NAD and FAD are reduced, ATP is made by substrate level phosphorylation.
Pyruvate dehydrogenase
The enzyme that removes hydrogen atoms from pyruvate.
Pyruvate decarboxylase
The enzyme which removes a carboxyl group, which eventually becomes carbon dioxide, from pyruvate,
Acetyl coenzyme A
The product when coenzyme A accepts acetyl.
Oxidative phosphorylation
The formation of ATP by adding a phosphate group to ADP, in the presence of oxygen, which is the final electron acceptor.
Chemiosmosis
The flow of hydrogen ions through ATP synthase enzymes. The force of this flow allows the production of ATP. Occurs across the inner mitochondrial membrane during oxidative phosphorylation in respiration.
Proton motive force
Force produced as hydrogen ions flow, through ATP synthase channels, down their concentration gradient. The force cause ADP and Pi to combine and form ATP.
Anaerobic respiration
The release of energy from substrates, such as glucose, in the absence of oxygen.
Respiratory substrate
An organic substance that can be used for respiration.
Mole
The gram molecule mass of a substance. 180g glucose is one mole of glucose.
