Cellular respiration (anaerobic) Flashcards
What happens during anaerobic respiration in animals?
The first stage is glycolysis and pyruvate molecules are produced. In the absence of oxygen, pyruvate is converted into lactic acid- lactate. The total energy yield is 2 ATP molecules per glucose molecule. The loaded acceptor molecules NADH, that are produced in glycolysis are needed to drive the conversion of pyruvate to lactate.
What is the anaerobic process called in yeast?
Anaerobic fermentation in yeast is called fermentation where pyruvate is broken down into ethanol and carbon dioxide. The energy yield is 2 ATP.
What happens during fermentation?
Without oxygen, pyruvate is not metabolised by cellular respiration but undergoes fermentation where the pyruvate remains in the cytoplasm and is converted to waste products.
Fermentation oxidises NADH to NAD+ so it can be reused in glycolysis. It prevents the build up of NADH in the cytoplasm.
Is fermentation less efficient than aerobic respiration?
Fermentation is less efficient at using the energy from glucose since 2 ATP are produced per glucose compared to the 38 ATP produced by aerobic respiration- the waste products of respiration contain plenty of energy.
What happens when strenuous exercise occurs?
If the strenuous exercise continues, lactate builds up in the muscles, the pH falls and pain and muscle fatigue occur. When this exercise stops the oxygen supply to the muscles is adequate and anaerobic respiration stops- accumulated lactate is converted back to pyruvate and enters the Krebs cycle.
What is anaerobic respiration?
Anaerobic respiration is the chemical breakdown of glucose in the absence of oxygen. The final product in different organisms depends on the enzymes the posses.
