Light Dependnt Rection

Question 1

Where does light dependant reaction are place

Answer 1

Thylakoids of chloroplast

Question 2

Role of light in photoionisation

Answer 2

• chlorophylll absorb energy from light
• excites electrons causing them to be released from chlorophyll

Question 3

What occurs in the electron transfer chain

Answer 3

• Electrons released from chlorophyll more down a series of carrier proteins embedded in the thylakoid membrane
• via redox reactions loosing energy each step

Question 4

What is energy released from electrons used for

Answer 4

• Actively transport protons from stroma to thylakoid membrane
• creates electrochemical gradient

Question 5

How is ATP produced through electrochemical gradient

Answer 5

Potions via facilitated diffusion diffuse down electrochemical gradient via channel protein ATP synthase this cause ATP <— ADP + PI

Question 6

How is reduced NADP produced

Answer 6

• Excited electrons and transfer NADP to H+ protons from photolysis to NADPH
• occurs in stroma of chloroplast

Question 7

Describe photolysis

Answer 7

Splitting of water using light energy produces:
- protons - reduce NADP
- electrons, replace electrons lost from chlorophyll
- oxygen, used for respiration or diffuses out of leaf as waste

Question 8

Where do H+ and electrons used to reduce NADP come from

Answer 8

H+ = photolysis of water
Electrons = NADP acts as the final electron acceptor of the electron transfer chain