Factors affecting the rate of photosynthesis

Question 1

what is the importance of photosynthesis

Answer 1

• Photosynthesis is responsible for the production of oxygen and without green plants, there would be no oxygen to sustain life as we know it.
• Photosynthesis absorbs carbon dioxide, which keeps the levels in the atmosphere constant. Greenplants are very important in the fight against rising CO2 levels, a major component of global warming.
• Green plants are important for the production of food for heterotrophic organisms.
• Photosynthesis also makes chemical energy available for the functioning of cells in plants.

Question 2

how can light intensity affect the rate of photosynthesis

Answer 2

• Without enough light (low levels of light), a plant cannot photosynthesise very quickly, and photosynthesis starts toslow downeven if there is plenty of water and carbon dioxide available.
• With increased levels of light intensity, the rate of photosynthesis will initially increase butonlyup to amaximum levelwhere, if the light intensity becomes too high, the stomata will close.

Question 3

how can Carbon Dioxide concentration affect the rate of photosynthesis

Answer 3

Adecreaseincarbon dioxide concentrationleads to adecreasein therate of photosynthesis, whereas anincrease in carbon dioxide concentration leads to anincrease in the rate of photosynthesis.

Question 4

how can Temperature affect the rate of photosynthesis

Answer 4

Plants photosynthesise at their best at25 °C. Temperatures that aretoo highortoo lowinhibittherate of photosynthesis. Low temperatures cause enzymes to become inactive, whereas high temperatures cause the stomata to close in order to limit the loss of water.

Question 5

how does the rate of Photosynthesis affect crops

Answer 5

The greater the rate of photosynthesis, the greater the rate of productivity, which means larger crops and more food.

Question 6

how does a greenhouse work to help plants grow

Answer 6

Warmth and humidity promote plant growth. Plants need moisture, warmth and light to grow. By trapping heat and light, a greenhouse stabilizes the growing environment by buffering the ambient temperature and protecting plants from extreme cold. This aids in plant growth.

Question 7

what is greenhouse

Answer 7

A greenhouse is a glass or plastic building in which plants that need protection from cold weather are grown. Warm air is trapped inside the greenhouse and the aim of a greenhouse is to provide optimal conditions for light, temperature, and carbon dioxide, to ensure that the plants grow to their maximum potential in order to improve crop yields.

Question 8

how is a greenhouse designed

Answer 8

• greenhouses must be designed to allow themaximum amount of lightto reach the plants, hence transparent materials such as glass or plastic are normally used.
• optimal growth temperaturemust be maintained to improve crop yields and this can be done by either using heating devices when the temperature is too low, or high temperatures can be decreased by improving ventilation within the greenhouse.
• Carbon dioxide enrichment can be used in greenhouses to increase therateandqualityof photosynthesis. During the day, the carbon dioxide levels can decrease greatly due to the light phase of photosynthesis. CO2can be increased by either largescale pumping of CO2gas from tanks into the greenhouse or by the addition of sodium bicarbonate and organic materials to the soil.

Question 9

a summery on why the way we build greenhouses is great for photosynthesis

Answer 9

• The glass roof or plastic walls lets a lot of light into the greenhouse and helps to trap heat inside (This helps a lot in winter times).
• Carbon dioxide levels can be increased by adding sources of CO2because of the enclosed environment.
• Watering is also more efficient because vapour is trapped and causes the air in the greenhouse to become humid, which means less water is lost.
• Pests can also be more easily controlled.