Photosynthesis

Question 1

Photosynthesis

Answer 1

Converting light energy to chemical energy

Occurs in plants, algae, some protists, prokaryotes

6CO2 + 6H20 -> C6H1206 + 6O2

Question 2

Autotroph

Answer 2

Makes organics

Example- Photosynthesis

Question 3

Heterotroph

Answer 3

Obtains food from other organisms

Question 4

Leaves

Answer 4

Major site of photosynthesis

Question 5

Chloroplasts

Answer 5

Where photosynthesis occurs

Contains thylakoids and grana

Split water into hydrogen and oxygen, incorporate electrons of hydrogen into sugar molecules

Question 6

Redox Reaction

Answer 6

Water oxidized

Carbon dioxide reduced

Question 7

Light Receptors/ Pigments

Answer 7

Absorbs visible light

Colours we see are reflected (e.g. reflect green)

Question 8

Chlorophyll A

Answer 8

Main photosynthetic pigment

Question 9

Chlorophyll B

Answer 9

Accessory pigment

Question 10

Chlorophyll

Answer 10

Other accessory pigments other than A and B that absorb different wavelengths of light

Absorbs light and goes from ground state to unstable excited state

Gives off heat and light when excited

Question 11

Photo-systems

Answer 11

Light harvest complex -pigment on proteins

Funnel energy to reaction centre -> reaction centre chlorophyl absorbs energy -> bumps electrons up to electron acceptor

Question 12

Photosystem II

Answer 12

Excites electrons

O2 out as waste
H+ out to ATP synthase

Makes ATP -> to calvin cycle

Question 13

Photosystem I

Answer 13

Excites electrons

Accepts H+

Converts NADP to NADPH -> to calvin cycle

If we don’t need sugar, just ATP we just use system I (alternative to cellular respiration for leaves)

Question 14

Chloroplasts vs. Mitochondria

Answer 14

Both Make ATP using chemiosmosis/ETC

Different source of energy - NADH/FADH2 or light energy

Redox reactions

Different end goal

Question 15

Calvin Cycle

Answer 15

Anabolic (similar to TCA cycle)

Uses ATP and NADPH

Converts CO2 to sugar

Occurs in stroma

3 Phases - Carbon fixation, reduction, regeneration of CO2 acceptor

3 CO2 in, 6 NADPH in, 6 ATP in

1 3Carbon sugar out

Question 16

Regeneration

Answer 16

Phase 3 of Calvin Cycle

Uses 3 ATP

Reforms rubisco

Question 17

C4 Plants

Answer 17

Minimize cost of photorespiration

Stores CO2 in 4 carbon compounds in mesophyll cells

Question 18

Stomata

Answer 18

Guard cells that open and close to control CO2 and O2

Close stomata to conserve water, limits acces to CO2, and O2 builds up (slows down light reaction)

Question 19

CAM Plants

Answer 19

Open stomata at night

Stores CO2 in organic acids

During day CO2 released for Calvin Cycle