Photosynthesis

Question 1

Describe photosynthesis

Answer 1

The conversion of sunlight into chemical energy carbon dioxide and water and light = glucose and oxygen

Question 2

what are 2 physiological mechanisms of photosynthesis

Answer 2

1. Light reactions
2. Calvin cycle ( Light independent)

Question 3

Describe the light reaction

Answer 3

goal: Convert light energy into chmeical energy
* Chlorophyll absorbs light (photon)
* the photon passes energy (electron) along a series of pigments in the thylakoid membrane in the chloroplasts.
* The pigments capture light energy and pass it along.
* This moves to a reaction centre where light energy is converted via proteins to: oxygen + NADPH + ATP

Question 4

Describe the calvin cycle (light independent reaction)

Answer 4

• Use stored chemical energy to”fix” co2 and create a product that can be converted into glucose
• in the stroma
• NADPH + ATP with co2 to produce glucose its products are ADP + G3P + NADP+

Question 5

Environmental factors that effect photosynthesis

Answer 5

Light intensity - inc rate of photosynthesis until a saturation point
Leaf size - increased number of chlorophyl to produce chemical energy
Disease - reduces rate as leaf discoloured
Temp - 25-35 - inc rate in optimum range high temps will denature enzymes
Nutrient availability - e.g Nitrogen are key for chlorophyll production

Question 6

Cultural factors that effect photosynthesis

Answer 6

Canopy management - Removing leaves to optimize light penetration and air circulation - overly dense reduce shading
irrigation - defecit irrigation help to keep the stomata open while reducing excessive growth