Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Photosynthesis is the process by which green plants synthesize their own food using sunlight, water, and carbon dioxide () from the air.
Air provides the essential gas Carbon Dioxide () which acts as a carbon source for the production of glucose ().
Plants take in air through tiny pores called stomata, which are primarily located on the underside of the leaves.
The opening and closing of stomata are regulated by guard cells, which control the amount of entering the plant and the amount of water vapor leaving it.
During the preparation of food, plants release Oxygen () into the air as a byproduct, which is vital for the survival of all living organisms.
The concentration of in the atmosphere can influence the rate of photosynthesis; higher concentrations (up to a certain limit) generally increase the rate of food production.
📐Formulae
💡Examples
Problem 1:
Explain what happens to the food production process if a plant is kept in a sealed glass jar without any source of fresh air.
Solution:
The rate of photosynthesis will eventually decrease and stop once the available inside the jar is exhausted.
Explanation:
Plants require a continuous supply of from the air to perform photosynthesis. In a sealed environment, the plant consumes the limited to produce glucose (). Once the level drops to zero, the chemical reaction cannot proceed, regardless of the presence of sunlight and water.
Problem 2:
Why do plants grow faster in some greenhouses where is artificially pumped into the air?
Solution:
Increasing the concentration of enhances the rate of photosynthesis.
Explanation:
Since is a raw material in the equation , providing more 'fuel' in the form of air enriched with carbon dioxide allows the plant to produce more glucose and grow more rapidly, provided light and water are also sufficient.