Respiration
Cellular respiration is the process that releases energy from glucose in every living cell, mainly in mitochondria.
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Cellular respiration is the process that releases energy from glucose in every living cell, mainly in mitochondria.
- Aerobic respiration needs oxygen
- Glucose plus oxygen gives carbon dioxide, water and energy
- Energy is stored as ATP
🧠 Quick quiz
Three questions. Score 2 or more to complete the topic.
What is Respiration?
Within Biology, which covers cells, the human body, genetics, evolution, plants and ecosystems: the science of living things, this topic explains Respiration. Biology topics show how living things work, from the cell up to whole ecosystems, with models you can explore step by step.
Check that you can explain Respiration in your own words and give one example from everyday life. If you can do that, you have understood the core idea.
Understanding Respiration helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
Respiration in detail
Respiration is the process that releases energy from food in all living cells. Aerobic respiration uses oxygen: glucose + oxygen → carbon dioxide + water + energy (C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O). Most of it takes place in mitochondria. It is an exothermic reaction.
The energy is used for muscle contraction, building molecules, active transport and keeping a constant body temperature. Respiration is not the same as breathing, which is the movement of air. Cells with high energy demands, such as muscle and nerve cells, have many mitochondria. Plants respire day and night.
How the interactive helps you understand Respiration
Watch the reaction model in the interactive. Use any sliders or buttons it offers to change the values and see how the reaction model responds.
Before you change anything, predict the result. Then change one value at a time and check whether your prediction was right. This is a quick way to build a correct mental model of Respiration.
Real-life uses and examples
- Explain how Respiration helps a living thing stay alive, using a plant or animal example.
- Connect Respiration to health, food and medicine in everyday life.
- Use Respiration to interpret a diagram, graph or microscope image from a practical.
Common mistakes to avoid
- Using everyday words, such as “energy” or “bad”, without their scientific meaning.
- Listing the steps of a process without saying how one step causes the next.
- Learning the definition without testing it. Use the quiz and the interactive to check that you can apply the idea.
Frequently asked questions about Respiration
What is Respiration?
Cellular respiration is the process that releases energy from glucose in every living cell, mainly in mitochondria.
What are the most important points about Respiration?
The main points are: Aerobic respiration needs oxygen; Glucose plus oxygen gives carbon dioxide, water and energy; Energy is stored as ATP.
Why is Respiration useful?
Understanding Respiration helps you explain how living things stay alive and respond to their surroundings, which is central to biology exams.
How can I practise Respiration?
Open the interactive at the top of this page and change the controls one at a time. Predict the result before each change, then take the three-question quiz. A score of two or more marks the topic as complete on this device.
Which topics are related to Respiration?
Related topics in Biology include Gas Exchange in Alveoli, The Heart, Heart Disease.