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They key points covered in this video include:
1. Respiration
2. Why is respiration important?
3. Aerobic Respiration
4. ATP


Respiration is a process that happens continuously in all living cells – cells are constantly supplied with energy. Respiration is exothermic. This means that energy is released to the environment when respiration takes place. There are two types of respiration – aerobic and anaerobic respiration. Both are catalysed by enzymes. In cellular respiration organisms use the breakdown of organic compounds like glucose to fuel metabolic processes. Metabolic processes are the necessary chemical reactions in living organisms. This enables organisms to grow, keep their heart beating and move around.

Why is Respiration Important?

Organisms build up (or synthesise) larger molecules from smaller ones – like starch from glucose. The energy is also used to contract muscles so organisms can move about. We also use energy to keep our body temperature at a constant level – if it’s too high or low it can harm the organism. Organisms increase their rate of respiration in cold environments to maintain a constant temperature as respiration transfers energy by heating.

Aerobic Respiration

Aerobic respiration uses oxygen and glucose. It takes place in the mitochondria. The reaction that takes place is. This can also be written as. Aerobic respiration is the most efficient way of transferring energy from glucose.


Energy actually comes in the form of the chemical molecule ATP. ATP stands for Adenosine Triphosphate. All living organisms use ATP for energy. Energy is just a simplified term for ATP.


1. Energy is transferred to organisms through respiration
2. Respiration happens continuously
3. It’s used for metabolic processes
4. We need energy to keep our body temperature stable, for synthesising large molecule and to contract muscles for movement
5. Aerobic respiration uses oxygen and glucose
6. The word equation for aerobic respiration is:
glucose + oxygen → carbon dioxide + water
7. The chemical equation for aerobic respiration is:
C6H12O6 + 6 O2 → 6 CO2 + 6H20
8. Energy comes in the form of ATP
9. When we talk about energy in out body, we really mean ATP