Photosynthesis Process

Question 1

What is photosynthesis?

Answer 1

The conversion of light energy, carbon dioxide, and water into high energy compounds (i.e glucose)

Question 2

What is the general equation for photosynthesis?

Answer 2

CO2 + H2O + light energy creates [CH2O]n + O2

Question 3

How does light enter a plant?

Answer 3

Enters plant cells from the top cuticle of the leaf

Question 4

How does water enter the plant?

Answer 4

Absorbed by plant root, delivered to leaf vis vascular xylem bundle

Question 5

How does CO2 enter the plant?

Answer 5

Gets into leaf via stoma (controlled by guard cells)

Question 6

Structure of chloroplasts

Answer 6

Has 2 membranes which surrounds the stroma fluid, has stacks of thylakoids called granum

Question 7

Where does the light reactions take place in?

Answer 7

Thylakoids

Question 8

What occurs in the light reaction stage?

Answer 8

Light is absorbed by chlorophyll which drives helps create ATP and NADPH

Question 9

Step 1 in light reaction stage

Answer 9

Light energy causes H2O to split into 1/2O2 and 2H+, released e- goes through photo system 1 (thylakoids membranes)

Question 10

Step 2 in light reaction stage

Answer 10

The e- movement through the photo systems allows for H+ to be pumped inside the inner membrane/ lumen, an H+ gradient is formed

Question 11

Step 3 in light reaction stage

Answer 11

In photo system 2 e- moves through to change NADP+ to NADPH (goes to stroma)

Question 12

Step 4 in light reactions stage

Answer 12

The conc gradient of H+ formed (high in lumen, low in inter membrane space) allows for H+ to enter ATP synthase enzyme to convert ADP to ATP

Question 13

What happens in the Calvin cycle?

Answer 13

Uses NADPH and ATP prod in light reactions to reduce CO2 to carbs such as glucose (light-independent) (anabolic reactions)

Question 14

Where does the Calvin cycle occur?

Answer 14

Stroma of chloroplasts

Question 15

Phase 1 of the Calvin cycle

Answer 15

Carbon fixation: catalyzed by rubisco enzyme, 3carbon is fixed to 3RuBP and splits into 2 3-PGA (x3 therefore 6 3-PGA)

Question 16

Phase 2 of Calvin cycle

Answer 16

Reduction: the 6 3-PGA receives phosphate from 6 ATPs and red. by 6 NADPHs to create 6 G3Ps

Question 17

Phase 3 of Calvin cycle

Answer 17

Regeneration: 5 G3Ps are recycled to regenerate 3 RuBP, 1 exits to go on to make glucose

Question 18

How much NADPH was used in total?

Answer 18

6

Question 19

How much CO2 was used in total?

Answer 19

3

Question 20

How much ATP was used in total?

Answer 20

9 (6 in reduction, 3 in regeneration)