8.1 Overview of Photosynthesis

Question 1

Define Photosynthesis

Answer 1

• The process whereby light energy is converted to chemical energy
• Stored in glucose or other organic compounds

Question 2

Photosynthetic organisms

Answer 2

• Plants (mosses ferns flowering plants)
• Algae (kelp)
• Protists (euglena sp.)
• Bacteria (Purple bacteria and cyanobacteria - oscillatoria & nostoc)

Question 3

Overall equation of photosynthesis

Answer 3

12 H2O + 6 CO₂ +18 ATP + 12 NADPH
->
6O2 + C6H12O6 + 6 H2O + 18 ADP + 12 NADP+ + 18Pi

Question 4

Site of photosynthesis

Answer 4

In leaves (thylakoid membrane)

Question 5

Leaves contain

Answer 5

• chloroplast: which contains photosynthetic pigments in thylakoid membrane

Question 6

Photosynthetic pigments ada 2 jenis which are

Answer 6

1. Main Pigment
2. Accessory Pigments

Question 7

Main pigments (ada 1) which is:

Answer 7

1. Chlorophyll a
   • kaler blue green
   • absorbs: violet & red
   • reflect: green

Question 8

Function main pigment?

Answer 8

Initiates light dependent rxn

Question 9

Accessory Pigments ada 2 which are:

Answer 9

1. Chlorophyll b
   - kaler yellow green
   - absorbs: violet blue & red
2. Carotenoids
   - kaler yellow orange red brown
   - e.g. carotene
   - absorbs: violet-blue & blue-green
   - reflects: orange & yellow.

Question 10

Function of accessory pigments

Answer 10

Broaden colour spectrum to be used for photosynthesis

Question 11

Function of carotenoids

Answer 11

For photoprotection
(Protect chlorophyll from excessive light)

Question 12

Why do leaves appear green?

Answer 12

1. Photosynthetic pigments at the membrane of thylakoid
2. absorbs: violet blue and red light
3. reflects: green light