Energy from respiration Flashcards
How may the energy released during aerobic respiration be used by an organism? (4)
1) To build larger molecules from smaller ones.
2) To enable muscle contraction in animals.
3) Maintain a constant body temperature in colder surroundings.
4) Build sugars, nitrates and other nutrients into amino acids and then proteins in plants.
Where do most of the chemical reactions of aerobic respiration take place?
What are they controlled by?
Most of the chemical reactions of aerobic respiration take place in mitochondria, controlled by enzymes.
Give the word equation for aerobic respiration.
glucose + oxygen => carbon dioxide + water [+energy]
What two main affects does exercise have on the body and why?
1) The heart rate increases and the blood vessels supplying muscles dilate to allow more blood containing oxygen and glucose to reach the muscles.
2) Breathing rate and depth of each breath increases, this allows a greater uptake of oxygen and release of carbon dioxide at the lungs.
How can muscles store glucose, what happens to this stored glucose when we exercise?
Muscles can store glucose as glycogen, the glycogen can be converted back to glucose for use during exercise.
What happens to muscles if they are used over a long period of time?
They will get tired or fatigued and stop contracting efficiently.
What happens when muscles cannot get enough oxygen for aerobic respiration?
They respire anaerobically.
What is produced in anaerobic respiration and why?
Lactic acid is produced as glucose is not completely broken down, anaerobic respiration is not efficient.
What does lactic acid cause?
How can lactic acid be broken down?
What is oxygen debt?
What does oxygen do to lactic acid?
Lactic acid causes muscle fatigue.
Lactic acid can be broken down by the flow of blood bring oxygen to the muscles.
The oxygen debt is the oxygen required to break down lactic acid after exercise.
Oxygen oxidises lactic acid into carbon dioxide and water.
