Chapter 12 - Respiration Flashcards
What is respiration?
Respiration is a chemical process that involves the breakdown of nutrient molecules (specifically glucose) in order to release the energy stored within the bonds of these molecules. Respiration is enzyme controlled.
Why is respiration needed?
Respiration is needed for muscle contraction, protein synthesis, cell division, growth, active transport across cell membranes, generation of nerve impulses and maintaining a constant body temperature.
How can respiration be tested in yeast?
Methylene blue dye is a suitable indicator for testing respiration in yeast. The time taken for the methylene blue to discolour is a measure of the rate of reaction of the yeast cells.
What is aerobic respiration?
Aerobic respiration is the chemical reaction in cells that use oxygen to break down nutrient molecules to release energy. Glucose + oxygen → carbon dioxide + water. C6H12O6 + 6O2 → 6CO2 + 6H2O.
What is anaerobic respiration?
Anaerobic respiration is the chemical reactions in cells that break down nutrient molecules to release energy without using oxygen. It releases much less energy per glucose molecules than aerobic respiration
How is anaerobic respiration used in yeast?
Anaerobic respiration can be used in yeast by using it in bread making where the carbon dioxide produced causes the dough to rise or in brewing where the ethanol produces gives the beet its alcoholic nature and the carbon dioxide produces gives the beer its fizz. Glucose → alcohol + carbon dioxide. C6H12O6 → 2C2H5OH + 2CO2.
How is anaerobic respiration used in animals?
Anaerobic respiration is used in animals during vigorous exercise when out muscles have a higher demand for energy. Glucose → lactic acid. Lactic acid builds up in muscles and blood during vigorous exercise causing an oxygen debt. After exercise, you continue to have a fast heart rate to transport the lactic acid in the blood from the muscles to the liver, you continue to have a faster and deeper breathing rate to supply oxygen for aerobic respiration of lactic acid which occurs in the liver.
