Photosynthesis
Green pigment found in plants necessary for trapping light energy
for photosynthesis. Contains the element magnesium. Made in
chloroplasts.
A specialised cell organelle (plastid) containing chlorophyll. They are
green in colour and function during photosynthesis. They are
composed of grana (used during the light stage) and stroma (used
during the dark stage) of photosynthesis.
Takes place in the stroma of the chloroplasts. Is a light independent
stage, i.e. it can take place in the presence or absence of light. The
function of this phase is the reduction of carbon dioxide (CO2), i.e.
adding hydrogen (H) to CO2 to form a carbohydrate (CHO) – glucose.
It is an endergonic process. Energy (ATP) produced during the light
phase is used here; hydrogen, supplied by NADPH2, is used to reduce
CO2.
To remove starch from (usually a plant for experimental purposes).
Place plant in dark container for 48 hours. This allows starch,
manufactured during photosynthesis, to be translocated away from
the leaves and also prevents the production of any further starch.
During photosynthesis and aerobic respiration, a high energy
electron is transferred along a series of chemicals (carriers). At each
transfer, sufficient energy is lost from the electron to convert ADP
into ATP.
Plant used in photosynthesis experiments. Grows under water.
Count the number of bubbles given off in a certain time = rate of
photosynthesis.
chlorophyll
chloroplast
dark phase (stage)
destarch
electron transport
system
Elodea canadensis
(Canadian
pondweed)
Refers to chemical reactions that require an energy input to start
them, e.g. photosynthesis.
endergonic
A chemical reaction where heat energy is taken in from the
surroundings to make the reaction work, e.g. photosynthesis.
endothermic
Substances that transport hydrogen in biological reactions by
reduction and oxidation, e.g. during the light phase of
photosynthesis, NADP is reduced to NADPH2 and is carried into the
dark phase where it is oxidised and the NADP returns to the light
phase to be reduced again. They are also used in respiration.
This takes place in the grana of the chloroplasts. Its functions are:
 to produce ATP
 to produce hydrogen atoms
Both of these will be used in the dark phase for the reduction of
carbon dioxide and production of carbohydrate.
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hydrogen
carrier(s)
light phase (stage)
An oxidising and reducing co-enzyme necessary in photosynthesis. It
traps and transfers hydrogen ions in cell activities.
NADP
nicotinamide
adenine
dinucleotide
phosphate
A chemical reaction in which oxygen combines with another
substance.
OR A reaction which involves the removal of hydrogen from a
compound.
OR A reaction that involves the loss of electrons.
oxidation
The addition of phosphorus (phosphate), i.e. ADP + P = ATP.
phosphorylation
The process in plants that makes food using light energy. It occurs in
the chloroplasts of green plants in which carbon dioxide and water,
in the presence of light energy and chlorophyll, are converted into
simple sugars and oxygen. The light energy is converted to chemical
energy and is stored in the sugar molecule.
A chemical reaction in which hydrogen combines with another
substance.
OR A reaction which involves the removal of oxygen from a
compound.
OR A reaction that involves the gain of electrons.
Emitted from the sun as electromagnetic waves . It is capable of
being absorbed by the pigment chlorophyll in the chloroplasts of
plant cells.
Combining separate small units to form a more complex structure,
e.g. elements to molecules; amino acids to proteins;
monosaccharides to polysaccharides; etc.
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photosynthesis
reduction
solar energy /
radiation
synthesis(e)