B8 - Photosynthesis

What is photosynthesis?

Photosynthesis is the process by which green plants and some other organisms use sunlight to synthesize foods with the help of chlorophyll in their cells.

What is the word equation for photosynthesis?

Carbon dioxide + water + light energy → glucose + oxygen.

What are the chemical formulas for carbon dioxide, water, oxygen, and glucose?

Carbon dioxide: $CO_2$, Water: $H_2O$, Oxygen: $O_2$, Glucose: $C_6H_{12}O_6$.

Why is photosynthesis an endothermic reaction?

Photosynthesis is endothermic because it requires energy from sunlight to convert carbon dioxide and water into glucose and oxygen.

What is translocation in plants?

Translocation is the movement of nutrients, particularly glucose, throughout the plant in phloem tissue.

What role do different plant tissues play in translocation?

• Phloem: transports sugars from leaves to other parts of the plant.

• Xylem: transports water and minerals from roots to leaves.

What are the limiting factors of photosynthesis?

The main limiting factors include light intensity, carbon dioxide concentration, and temperature.

How do graphs of photosynthesis rate show limiting factors?

Graphs typically demonstrate that if one factor increases while others remain constant, the photosynthesis rate increases until another factor becomes limiting.

How are limiting factors important to the economics of greenhouses?

Optimizing conditions such as light, CO2, and temperature in greenhouses can maximize crop yield and economic benefits.

What is the inverse square law in the context of light intensity and photosynthesis?

The inverse square law states that the intensity of light is inversely proportional to the square of the distance from the light source: as you double the distance, the light intensity becomes one-fourth.

How is glucose produced in photosynthesis used by plants?

Glucose is used for energy (respiration), converted into starch for storage, or used to synthesize other organic compounds.

What is the required practical to investigate the effect of light intensity on the rate of photosynthesis?

In the practical, an aquatic organism like pondweed is placed in water, and a light source is varied in distance to measure the rate of photosynthesis, typically by counting oxygen bubbles produced.