ATP – raw material that supplies carbon atoms to be fixed into carbohydrate (e)
Carbon dioxide – high energy compound that provides energy to drove carbon fixation (d)
Carbon fixation – production of ATP using energy trapped during a light dependant reaction (b)
Chemical – form of energy contained in carbohydrate formed by photosynthesis (p)
Cellulose – complex carbohydrate used to construct plant cell walls (n)
Chlorophyll – green pigment that traps light energy (a)
Chloroplast – discus-shaped structure in a cell of a green leaf (j)
Glucose – 6-caron sugar molecule formed by photosynthesis (k)
Hydrogen – product of photolysis of water needed during carbon fixation (m)
Light – form of energy trapped by chlorophyll for photosynthesis (o)
Limiting factor – general term for a factor whose restricted supply prevents an increase in the rate of a process (l)
Oxygen – by product of photolysis of water needed for aerobic respiration (h)
Photophos. – stage of photosynthesis that results in formation of carbohydrate (g)
Photolysis – light dependant stage of photosynthesis (f)
Starch – complex carbohydrate stored in plant cells (c)
Water – raw material that becomes split into oxygen & hydrogen during photosynthesis (i)
5 Marker – Describe what happens during the two stages of photolysis & carbon fixation
In photolysis, the light energy absorbed by chlorophyll is used to split water molecules into hydrogen & oxygen. Light energy is also used to synthesise ATP from ADP & inorganic phosphate. In carbon fixation the hydrogen & ATP produced in photolysis are usedin this second stage. In a series of reactions the hydrogen combines with carbon dioxide from the air to create glucose. ATP provides the energy needed for this synthesis. The series of reactions is controlled by enzymes & takes place in the chloroplast.
1. Energy is measured in units called kilojoules.
2. Glucose is the main...