Photosynthesis

Question 0

Photosynthesis reaction

Answer 0

6CO2 + 6H2O -> C6H12O6 + 6O2

• exact reverse of respiration
• reduces carbon dioxide and oxidizes water into oxygen
• we take up oxygen… But plants are opposite and produce oxygen

Question 1

Photosynthesis uses the sun’s energy to make??

Answer 1

Carbohydrates

Question 2

Photosynthesis can be broken down into:

Answer 2

1. Light reactions (happen first) require light

2. Dark reactions- dont only happen in the dark, but they dont require light

Question 3

Light reactions

Answer 3

• Use sunlight
• oxidize water into O2
• this makes alot of ATP and NADPH
• goal is to make alot of energy in the form of ATP and NADPH

Question 4

Dark reactions

Answer 4

• takes CO2 out of the air and uses it to make carbohydrates

- costs alot of energy (uses the ATP and NADPH)

Question 5

Where does photosynthesis take place

Answer 5

-in the chloroplasts of plants

Thylakoid lumen and membrane

Question 6

Chloroplast structure

Answer 6

• have multiple membranes
• have an inner and outer membrane
• had a thylakoid membrane containing grana
• three membranes
• —photosynthesis takes place in the thylakoid lumen and membrane

Question 7

How many times is light involved in photosynthesis?

Answer 7

• twice

- once in photosystem 2 and once in photosystem 1

Question 8

Light reactions system

Answer 8

-PS2 absorbs light best at 680
-PS1 absorbs light best at 700
-passes the excited electrons from
1. photosystem 2 to
2. plastoquinone(a carrier) which passes them onto
3. cytochromr b6f complex who passes them off to
4. plastocyanine who passes them off to
5. photosystem 1 which requires light and passes them to
6. Faradoxin that passes them to a
7 FMR complex which uses those electrons to make NADPH

***take place in the thylakoid lumen

Question 9

Which photosystem is involved first?

Answer 9

PS2 then PS1

Question 10

Where is water converted into O2?

Answer 10

At PS2

Question 11

Final electron carrier

Answer 11

NADPH

Question 12

[H+] concentration

Answer 12

High on the lumen side (lower PH)
Low on stroma side (higher PH)

This is used to produce ATP

Question 13

Dark reactions system

Answer 13

1. Turn CO2 into GA3P (3 carbons) so it needs 3 CO2 molecules
   - –costs 9ATP and 6NADPH very expensive
   - the GA3P is used to make carbohydrates

Question 14

What is the calvin cycle?

Answer 14

Another name for the dark reactions

Question 15

RuBisc

Answer 15

The enzyme that starts the dark reactions

-one of the most abundant protein/enzyme on the planet

Question 16

Carbon fixation

Answer 16

3CO2 + H2O -> GA3P

-uses alot of ATP and NADPH from the light reaction