6.4 **Higher Only** - Interaction of Limiting Factors in Photosynthesis Flashcards
How can you calculate the rate of photosynthesis?
By measuring the oxygen production of a plant during an experiment.
What is the setup for measuring oxygen production in plants?
Pondweed is placed in a test tube full of water, sealed with a bung, and connected to a capillary tube leading to a syringe.
What role does the lamp play in the experiment?
A lamp is placed at a measured distance from the test tube to provide light for photosynthesis.
How is the volume of oxygen produced measured?
By measuring the distance the bubble has moved in the capillary tube using a ruler.
What variables can be changed to observe their effect on photosynthesis?
Temperature, time the pondweed is left, and light intensity.
What is a limiting factor in photosynthesis?
An environmental condition that restricts the rate of photosynthesis when at low levels.
What happens to the rate of photosynthesis when a limiting factor is present?
The rate will not increase despite increases in other factors.
How is a graph used to represent limiting factors in photosynthesis?
A graph with one line leveling off indicates one limiting factor, while two lines represent two limiting factors in two experiments.
What unit is used to measure light intensity?
Light intensity is measured in lux.
What was the limiting factor in the photosynthesis experiment at 50 lux?
The limiting factor was light intensity.
How did the light intensity of 50 lux affect photosynthesis compared to 100 lux?
At 50 lux, the rate of photosynthesis was limited compared to the 100 lux experiment.
What potential effect could increasing light intensity have on photosynthesis?
Increasing light intensity could further increase the rate of photosynthesis.
What does a graph involving three limiting factors show?
It shows three limiting factors, with another factor stated on each line, which is the same in each.
What is the limiting factor in photosynthesis?
The limiting factor is temperature as light intensity is the same in each and carbon dioxide is increasing.
How can farmers enhance photosynthesis in greenhouses?
Farmers can use the knowledge of limiting factors to enhance the conditions in the greenhouse for a greater rate of photosynthesis. This will increase growth leading to increased profits.
