Bioenergetics
Photosynthesis:
8.1 - Photosynthesis:
6CO2 + 6H2O → C6H12O6 + 6O2
Carbon dioxide + Water -> Glucose + Oxygen
It needs energy, takes place in chloroplast which contain chlorophyll and is an endothermic reaction.
Leaf adaptations are broad leaves for high surface area, short diffusion path, air spaces and guard
cells and veins to carry water in xylem to cells of leaves.
Algae carry out photosynthesis in water and have larger SA and absorb CO2 dissolved in water
around them. The released O2 is also dissolved.
8.2 - The Rate of Photosynthesis:
Limiting factor is the factor which limits photosynthesis.
Light – more light, more photosynthesis and vice-versa.
Temperature – High temperature = more photosynthesis until 40-50 degrees+ as enzymes begin to
denature and less photosynthesis happens.
Carbon Dioxide Concentration – More CO2 concentration = more photosynthesis and is typically the
limiting factor on a sunny day but at night CO2 levels go up.
Chlorophyll – When plants don’t have enough mineral, mainly Mg, a lack in chlorophyll can limit
photosynthesis.
8.3 - How Plants use Glucose:
Respiration – Glucose is used to respire to provide energy for cells. Respiration is reverse of
photosynthesis.
Cellulose – Glucose is turned into complex carbohydrates like cellulose to strengthen the cell wall.
Photosynthesis:
8.1 - Photosynthesis:
6CO2 + 6H2O → C6H12O6 + 6O2
Carbon dioxide + Water -> Glucose + Oxygen
It needs energy, takes place in chloroplast which contain chlorophyll and is an endothermic reaction.
Leaf adaptations are broad leaves for high surface area, short diffusion path, air spaces and guard
cells and veins to carry water in xylem to cells of leaves.
Algae carry out photosynthesis in water and have larger SA and absorb CO2 dissolved in water
around them. The released O2 is also dissolved.
8.2 - The Rate of Photosynthesis:
Limiting factor is the factor which limits photosynthesis.
Light – more light, more photosynthesis and vice-versa.
Temperature – High temperature = more photosynthesis until 40-50 degrees+ as enzymes begin to
denature and less photosynthesis happens.
Carbon Dioxide Concentration – More CO2 concentration = more photosynthesis and is typically the
limiting factor on a sunny day but at night CO2 levels go up.
Chlorophyll – When plants don’t have enough mineral, mainly Mg, a lack in chlorophyll can limit
photosynthesis.
8.3 - How Plants use Glucose:
Respiration – Glucose is used to respire to provide energy for cells. Respiration is reverse of
photosynthesis.
Cellulose – Glucose is turned into complex carbohydrates like cellulose to strengthen the cell wall.
