Respiration & Carbon Dioxide
- All living cells carry out some form of cellular respiration, from bacteria, to plants, to animals
- Many organisms carry out aerobic respiration
- Aerobic respiration requires the uptake of oxygen and produces carbon dioxide as a waste product
Aerobic respiration produces carbon dioxide as a waste product
- Because carbon dioxide is being constantly produced inside cells, a concentration gradient between the inside and the outside of cells is maintained
- Carbon dioxide leaves cells by diffusion
- This carbon dioxide is eventually released into the environment; either air or water
- Single-celled organisms release carbon dioxide by diffusion at the cell surface
- Terrestrial plants release carbon dioxide by diffusion from their stomata into the surrounding air
- Animals release carbon dioxide into the surrounding air or water by diffusion via their gas exchange surfaces e.g. mammalian lungs or fish gills