Respiration is the process by which cells release energy from glucose. This process occurs in the mitochondria within the cytoplasm of cells in all living organisms, including animals and plants.
It’s easy to mix up respiration with breathing, also known as ventilation. However, breathing is actually about inhaling and exhaling air to supply oxygen and remove waste, while respiration is a cellular process.
There are two types of respiration:
So if there’s plenty of oxygen around, aerobic respiration takes place. When oxygen is scarce, cells switch to anaerobic respiration.
The word equation for aerobic respiration is:
Glucose + Oxygen → Carbon Dioxide + Water
In other words, glucose is reacting with oxygen to form carbon dioxide and water. This reaction releases energy, so sometimes the equation may show energy in brackets.
For example, when we run:
Respiration and photosynthesis are opposite processes that are essential for the survival of living organisms. Respiration involves the breakdown of glucose to release energy. In contrast, photosynthesis is the process by which plants use energy from sunlight to convert carbon dioxide and water into glucose and oxygen.
Plants and other organisms use the glucose and oxygen produced during photosynthesis for respiration.
Plant respiration takes place in the dark and in the light. However, photosynthesis only takes place in the light.