Respiration

• Most of the energy we use to function comes from molecules of glucose, which were originally made by plants during photosynthesis.
• Cellular respiration is a process that transfers energy from glucose and is continuously occurring in living cells.
• Cellular respiration involves breaking apart glucose molecules to release the energy that's trapped inside.
• Exothermic means that the reaction releases energy before it occurs.
• Organisms use their energy for three main purposes: building up larger molecules from lots of smaller ones, muscular contraction, and maintaining body temperature.
• Aerobic respiration is the more common type and takes place whenever there's enough oxygen, it's the most efficient way to transfer energy from glucose and it takes place continuously in both plants and animals, specifically within the subcellular structures known as mitochondria.
• The word equation for aerobic respiration is glucose plus oxygen goes to form carbon dioxide plus water.
• Anaerobic respiration is respiration without oxygen, it's used when there's not enough oxygen to follow the demands of aerobic respiration, in this case, glucose goes to form lactic acid.
• Anaerobic respiration in plants and animals is different, in plants, glucose is converted to ethanol and carbon dioxide instead of lactic acid, this process is called fermentation and is used in industry for example, yeast is added to bread to produce carbon dioxide that forms little pockets of air that make the bread appear light and fluffy.
• Fermentation in yeast produces ethanol, a type of alcohol, which is used in beer and wine.