Photosynthesis

Question 1

Equation for the process of photosynthesis

Answer 1

6CO2 + 6H2O + Light Energy -> C6H12O6 + 6O2

Question 2

C3 plant

Answer 2

Calvin Cycle occurs in mesophyll cells.
Tend to lose more water due to stomatal opening
Converts two 3-carbon sugars into glucose
Eg Soybean

Question 3

C4 plants

Answer 3

Hot climates
Need to conserve water
Takes more ATP then normal to make sugar
Calvin cycle occurs in sheath cells
Enzymes scavenge CO2 to produce 4-carbon sugars

Question 4

CAM plants

Answer 4

Calvin cycle occurs at night
Stored as acid during night
Water loss is slowed by opening stomata only at night

Question 5

What are the three phases of Calvin cycle

Answer 5

1. Carbon fixation
2. Reduction
3. Regeneration of RuBp

Question 6

Calvin cycle

Answer 6

-Chemical energy and CO2 are used to produce organic compounds, such as glucose
-occurs in the stroma of chloroplasts
-3 phases

Question 7

1. Carbon Fixation

Answer 7

3 molecules of O2 join to 3 molecules of RuBp by rubisco
Results in the formation of 2 G3P

Question 8

2. Reduction

Answer 8

6 ATP and 6 NADPH are used to produce 1 net G3P
G3P + G3P -> Glucose

Question 9

3. Regeneration of RuBp

Answer 9

Every 3 molecules of CO2 fixed, 5 molecules of G3P are produced
Only 1 G3P exits the cycle to be used for the synthesis of carbs
Remaining G3P are used to regenerate RuBp

Question 10

Water splitting reaction

Answer 10

Also known as the light reaction, occurs in the thylakoid membranes of chloroplasts

Question 11

Water splitting reaction- Generation of O2

Answer 11

One of the primary products is molecular oxygen.
O2 is released into the atmosphere as a biproduct of photosynthesis
Is essential for aerobic respiration in organisms that need O2 for survival

Question 12

Water splitting reaction - Formation of high energy electron carriers

Answer 12

Water molecules are oxidised, leading to the release of electrons.
These are transferred through a series of electron carriers embedded in the thylakoid system
The movement of electrons generates a proton gradient across the thylakoid membrane which utilises to produce ATP

Question 13

Water splitting reaction - maintenance of photosynthesis

Answer 13

Water splitting reaction plays a crucial role in maintaining the stability of photosystem II
Which is responsible for capturing light energy & initiating electron transport chain