B4 - Bioenergetics (Limiting factors of the rate of photosynthesis (The…
B4 - Bioenergetics
Limiting factors of the rate of photosynthesis
The major limiting factors for photosynthesis are light intensity, temperature, and carbon dioxide levels.
An increase in the concentration of carbon dioxide gives an increase in the rate of photosynthesis. ... a rise in carbon dioxide levels has no affect on the rate of photosynthesis as the other factors such as light intensity become limiting.
Although the light dependent reactions of photosynthesis are not affected by changes in temperature, the light independent reactions of photosynthesis are dependent on temperature. They are reactions catalysed by enzymes. As the enzymes approach their optimum temperatures the overall rate increases.
Respiration and metabolism
Metabolism is the chemical processes that occur within a living organism in order to maintain life.
Aerobic respiration takes place in the mitochondria and requires oxygen and glucose, and produces carbon dioxide, water, and energy. ... This process requires oxygen and therefore following anaerobic respiration there is oxygen debt in the cell, as oxygen is needed to break down the lactic acid produced.
The energy produced during respiration is used in many different ways, some examples of what it is used for are: Working your muscles. Growth and repair of cells. Building larger molecules from smaller ones i.e. proteins from amino acids.
How light intensity increases photosynthesis
As light intensity increases, the rate of photosynthesis will increase as long as other factors are in adequate supply. As the rate increases, eventually another factor will come into short supply. The graph below shows the effect of low carbon dioxide concentration.
Uses of glucose from plants
Glucose is made in plants leaves using some for respiration
Releasing energy which enables it to convert the rest of the glucose into other substances
carbon dioxide + water —> glucose + oxygen + water.
6CO2 + 6H2O —> C6H12O6 + 6O2.
Effect of excersize on the body
your heart rate increases with physical activity to supply more oxygenated blood to your muscles. The fitter you are, the more efficiently your heart can do this, allowing you to work out longer and harder. As a side effect, this increased efficiency will also reduce your resting heart rate.