The Rate of Photosynthesis Flashcards
What does not enough light/CO2 do to the rate of photosynthesis?
Slows down the rate of photosynthesis.
What happens when light/CO2 levels are raised?
The rate of photosynthesis increases steadily - but only up to a certain point. Beyond that it won’t make a difference as the light intensity/CO2 increases (rate will no longer increase). This is because another factor will now be the limiting factor.
Why can temperature be the limiting factor if it is too low/high?
If too low - enzymes needed for photosynthesis work more slowly at low temperatures. If too hot - enzymes it needs for photosynthesis and its other reactions will be damaged (this happens at about 45 degrees Celcius)
What is the inverse square law?
Light intensity decreases in proportion to the square of the distance.
Equation:
light intensity ∝ 1 / distance (d)²
What is the most common way to artificially create the ideal environment for plants? Why?
Grow them in a greenhouse. Greenhouses help to trap the Sun’s heat and make sure that the temperature doesn’t become limiting.
Keeping plants enclosed in a greenhouse also makes it easier to keep them free from pests and diseases.
What may a farmer use in the winter and summer to keep the temperature at the ideal level?
Winter - heater to keep temperature at the ideal level.
Summer - could get too hot, might use shades and ventilation to cool things down.
What do commercial farmers use after the sun goes down and why?
Artificial light after the sun goes down to give their plants more quality photosynthesis time. (light is always needed for photosynthesis)
How can farmers and gardeners increase the level of carbon dioxide in the greenhouse?
E.g. by using a paraffin heater to heat the greenhouse. As the paraffin burns, it makes carbon dioxide as a by-product.
How can farmers provide all the minerals needed for healthy growth to a plant?
Add fertilisers to the soil.
Using additional items to get crop costs a lot. How is doing this justified?
If the farmer can keep the conditions just right for photosynthesis, the plants will grow much faster and a decent crop can be harvested much more often, which can then be sold.
Why is it important that a farmer supplies just the right amount of heat, light, etc. - enough for good plant growth but not more than is needed?
This would just be wasting money.
