Photosynthesis

Question 1

What is the balanced formula for photosynthesis?

Answer 1

6CO2 + 6H20 -> 6O2 + C6H12O6

Question 2

What are the two steps in photosynthesis?

Answer 2

Light-dependent reactions (thylakoid membrane, converts light into high energy molecules ATP and NADPH), Light-independent reactions (Calvin-cycle, stroma, uses high energy molecules ATP and NADPH to build carbohydrates (glucose))

Question 3

Where are pigments found? What are accessory pigments? What types are there?

Answer 3

In clusters in the thylakoid membrane, accessory pigments absorb different wavelengths of light, more energy can be used overall, transfer light energy to chlorophyll a, Chlorophyll a (dark green, only pigment that passes energy to electrons)
Chlorophyll b (light green)
Xanthophyll (yellow)
Carotenes (orange)

Question 4

What are the different wavelengths of light?

Answer 4

380/400nm (purple), 750nm (red)

Question 5

What are the most effective colours (for photosynthesis)? Least effective?

Answer 5

Blue and red, green (reflected)

Question 6

What is chromatography? How do you calculate it?

Answer 6

Separating plant pigments based on how soluble they are in a solvent (high up = more soluble), Rf = pigment/solvent

Question 7

What is the reduced form of NADP+?

Answer 7

NADPH

Question 8

What does Photosystem II do?

Answer 8

Thylakoid membrane, photolysis splits H2O, solar energy used to pass energy to e to proton pump while O2 diffuses out leaf, H+ produced help form proton gradient

Question 9

What does Photosystem I do?

Answer 9

Thylakoid membrane, after proton pump, e has low E, absorb photons for solar E re-energize e, NADP reduced by PSI giving it energy to make NADPH,

Question 10

What is Chemiosmosis?

Answer 10

Thylakoid membrane, build up of H ions in thylakoid space (lumen), moving H+ along the hydrogen gradient to the stroma, H+ can only move through ATP synthase, which uses H+ energy go make ATP from ADP + P

Question 11

What does the Calvin Cycle do?

Answer 11

6 cycles for 1 glucose, Uses NADPH, ATP and CO2 to make glucose, Carbon fixation (taken from “air” fixed into a molecule, RuBP (5 carbons) joins CO2 from atmosphere), Reduction (Hydrocarbon intermediate gets electrons from NADPH, NADPH oxidized to NADP+, ATP used to ADP, 2 Triose phosphate (G3P) created), Regeneration of RuBP (Triose phosphate combined to make RuBP using E from ATP), stroma

Question 12

What do all photosynthetic organisms have in common?

Answer 12

They all contain chlorophyll a

Question 13

What is produced as a result of photolysis?

Answer 13

Oxygen

Question 14

What is photolysis?

Answer 14

PSII, light energy used to split water into O2 and H