Living Organisms and Life Processes :
- Carbohydrates, fats and lipids are the main sources of this energy
- Harvested by the mitochondria present in each cell.
- It is not like that only foodstuff is sufficient for energy production but oxygen is also necessary.
- All these i.e. food stuffs and oxygen are transported up to the cell via circulatory system.
- Besides, it is coordinated by the control system of the body. i.e. each life process contributes in its own way in the process of energy production.
- Functioning of all these life processes also requires the energy.
- We get 4Kcal energy per gram of carbohydrates.
Living organism and Energy production :
- In living organisms, respiration occurs at two levels as
- body level
- cellular level.
- Oxygen and carbon dioxide are exchanged between body and surrounding in case of respiration occurring at body level.
- In case of respiration at cellular level, foodstuffs are oxidized either with or without help of oxygen.
- Energy is obtained in the form of ATP.
- For this purpose, glucose, a type of carbohydrates is oxidized step by step in the cells. This is called as cellular respiration.
- Cellular respiration occurs among the living organisms by two methods.
- Aerobic respiration (oxygen is involved)
- Anaerobic respiration (oxygen is not involved).