KS3 Science · Biology
Respiration
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Key words
Respiration A chemical reaction in cells that releases energy from glucose
Breathing Moving air into and out of the lungs
Aerobic respiration Respiration that uses oxygen
Anaerobic respiration Respiration without oxygen
Glucose The sugar that cells break down in respiration
Oxygen The gas that aerobic respiration uses up
Carbon dioxide The gas made in aerobic respiration and in fermentation
Mitochondria The parts of a cell where aerobic respiration happens
Lactic acid The product of anaerobic respiration in muscles
Oxygen debt The extra oxygen needed after hard exercise to break down lactic acid
Fermentation Anaerobic respiration in yeast
Yeast A fungus made of single cells, used to make bread and beer
Ethanol The alcohol made in fermentation
Microorganism A living thing too small to see without a microscope
Reactant A substance that is used up in a chemical reaction
Product A substance that is made in a chemical reaction
Word equation Shows the reactants and products of a reaction in words