Plants
Photosynthesis – plants and algae are the main producers of food which they synthesis from this
process. They are the primary producers of biomass in all food webs and chains
With an increase in temperature the rate of photosynthesis increases. It is controlled by enzymes and
this continues up to a certain temperature until the enzymes begin to denature and the ROR
decreases
For most plants the higher the light intensity the faster the ROR. co2 is also needed to make glucose
as the concentration increases the ROR increases.
a limiting factor is an environmental condition which in low levels restricts any increase in the rate of
photosynthesis. Despite increases in other factors the rate of photosynthesis will not increase any
more, the curve will level off
measuring the oxygen production of the plant will enable you to calculate the rate of photosynthesis
pondweed is placed in a test tube filled with water and the top is sealed with a bung.
A capillary tube also containing water leads into the test tube and it is attached to a syringe
A lamp is placed at a measured distance from the test tube
As it photosynthesises o2 is produced, forming a gas tube in the capillary tube
The distance the bubble has moved is measured using a ruler to calculate the volume of
oxygen produced
Many variables can be changed to observe their effect on photosynthesis, temperature using
a water bath, time the pondweed is left, the light intensity varied by the distance from the
lamp
Use knowledge of limiting factors to enhance conditions in greenhouse for a faster rate of
photosynthesis, increase growth leading to increased profits
The greater the intensity of light the more photons hit the chloroplasts in the leaf and the more
photosynthesis can occur
Root hair cells found in the tips of roots
Large permanent vacuole affects speed of movement of water from soil to cell
Xylem – specialised to transport water and mineral ions up the plant from the roots to the shoots:
when lignin is deposited it causes the cells to die and have become lignified, they become hollow and
are joined end to end to form a continuous tube so water and mineral ions can move through
phloem – specialised to carry products of photosynthesis to all parts of the plant
Cell walls of each cell form structures called sieve plates when they break down allowing
movement of substances from cell to cell
The cells in phloem are alive
Despite losing many sub cellular structures, energy these cells need to be alive is supplied by
mitochondria of the companion cells
Cells use this energy to transport sucrose around the plants
Transpiration is the loss of water from the leaves and stems of the plant as a consequence of gaseous
exchange which is done using the open stomata
Water evaporates at the open stomata on the surface of the leaves
Photosynthesis – plants and algae are the main producers of food which they synthesis from this
process. They are the primary producers of biomass in all food webs and chains
With an increase in temperature the rate of photosynthesis increases. It is controlled by enzymes and
this continues up to a certain temperature until the enzymes begin to denature and the ROR
decreases
For most plants the higher the light intensity the faster the ROR. co2 is also needed to make glucose
as the concentration increases the ROR increases.
a limiting factor is an environmental condition which in low levels restricts any increase in the rate of
photosynthesis. Despite increases in other factors the rate of photosynthesis will not increase any
more, the curve will level off
measuring the oxygen production of the plant will enable you to calculate the rate of photosynthesis
pondweed is placed in a test tube filled with water and the top is sealed with a bung.
A capillary tube also containing water leads into the test tube and it is attached to a syringe
A lamp is placed at a measured distance from the test tube
As it photosynthesises o2 is produced, forming a gas tube in the capillary tube
The distance the bubble has moved is measured using a ruler to calculate the volume of
oxygen produced
Many variables can be changed to observe their effect on photosynthesis, temperature using
a water bath, time the pondweed is left, the light intensity varied by the distance from the
lamp
Use knowledge of limiting factors to enhance conditions in greenhouse for a faster rate of
photosynthesis, increase growth leading to increased profits
The greater the intensity of light the more photons hit the chloroplasts in the leaf and the more
photosynthesis can occur
Root hair cells found in the tips of roots
Large permanent vacuole affects speed of movement of water from soil to cell
Xylem – specialised to transport water and mineral ions up the plant from the roots to the shoots:
when lignin is deposited it causes the cells to die and have become lignified, they become hollow and
are joined end to end to form a continuous tube so water and mineral ions can move through
phloem – specialised to carry products of photosynthesis to all parts of the plant
Cell walls of each cell form structures called sieve plates when they break down allowing
movement of substances from cell to cell
The cells in phloem are alive
Despite losing many sub cellular structures, energy these cells need to be alive is supplied by
mitochondria of the companion cells
Cells use this energy to transport sucrose around the plants
Transpiration is the loss of water from the leaves and stems of the plant as a consequence of gaseous
exchange which is done using the open stomata
Water evaporates at the open stomata on the surface of the leaves
