B2.4 Energy from respiration Flashcards
What is the equation for aerobic respiration?
glucose + oxygen —-> carbon dioxide + water (+energy)
What is the role of mitochondria in respiration?
The chemical reactions take place in the mitochondria of your cells
They have a folded inner membrane that provides a large surface area for the enzymes involved in respiration
What controls respiration?
Enzymes
Why do organisms respire?
RESPIRATION RELEASES ENERGY
Living cells need energy to carry out the basic functions of life-much of the energy released is used for ‘building’ activities(eg. building amino acids and then building these into proteins)
In animals the energy is used to make muscles contract-muscular activities require energy
mammals and birds keep their body at a constant temperature and require energy to either cool or heat up in thermoregulation
Why do you need more energy when you exercise?
When you use your muscles in exercise they start to contract harder and faster. More glucose and oxygen is needed to supply their energy needs
How does the body respond to exercise?
an increased heart rate, breathing rate and depth of breathing
glycogen stores in the muscle are converted to glucose for cellular respiration
the blood flow to the muscles increases
What are muscles made from?
Muscle tissue is made up of protein fibres
How do muscles work?
They contract when they are supplied with energy from respiration, they need a lot of energy to contract so they contain many mitochondria to carry out aerobic respiration to supply the energy needs
What is glycogen?
Muscles store glucose as the carbohydrate, glycogen.
It can be rapidly converted back to glucose during exercise.
What are the benefits of exercise?
Your heart and lungs benefit from exercise, they both become larger and develop a bigger and more efficient blood supply
This means they function as effectively as possible
What is anaerobic respiration?
Respiration without oxygen
glucose –> lactic acid + energy
Why does your body use anaerobic respiration?
When there is not enough oxygen for the muscle cells because the blood cannot supply oxygen fast enough
What is oxygen debt?
After exercise, oxygen is still needed to break down the lactic acid which has built up. The amount of oxygen needed in know as oxygen debt.
How can you tell when muscles respire anaerobically?
You will feel the effect of a lactic acid build up in your muscles. Lactic acid build up causes muscle fatigue
