Energy from respiration Flashcards
Aerobic respiration
The breaking down of food using oxygen to release energy for cells
glucose + oxygen →
glucose + oxygen → carbon dioxide + water + [energy]
Glycogen
A store of carbohydrates in animals, including the muscles, the liver and the brain
Anaerobic respiration
The breaking down of food without oxygen to release energy for the cells. It results in the incomplete breakdown of glucose to form lactic acid, so anaerobic respiration is not as efficient as aerobic respiration
glucose →
glucose → lactic acid + [energy]
Lactic acid
A product of anaerobic respiration - builds up in the muscles with exercise
Oxygen debt
The extra oxygen that must be taken into the body after exercise has stopped to complete the aerobic respiration of lactic acid
Where in the cells does respiration take place?
Inside the mitochondria, which have a folded inner membrane. This gives it a large surface area for enzymes to work on
What is the energy produced during respiration used for?
- Building larger molecules from smaller ones
- Enabling muscle contraction in animals
- To maintain a steady body temperature in colder surroundings for mammals and birds
- To build up sugars, nitrates and other nutrients into amino acids in plants, which are then built up into proteins
lactic acid + oxygen →
lactic acid + oxygen → water + carbon dioxide
How does the body respond to the increased demands for oxygen during exercise?
- It increases the heart rate, the breathing rate and the depth of breathing
- Glycogen stores in the muscle are converted to glucose for cellular respiration
- The blood flow to the muscles increases
Why do muscles use anaerobic respiration to obtain energy?
When muscles work hard for a long time they become fatigued and don’t contract efficiently. If they don’t get enough oxygen they will respire anaerobically
