Electron Flow in Light Reaction

Question 1

These are the functional units for photosynthesis

Answer 1

Photosystems

Question 2

Where are photosystems found?

Answer 2

Thylakoid membranes

Question 3

They are characterized by a particular pigment organization and association patterns whose work is the absorption and transfer of light energy, which implies transfer of electrons

Answer 3

Photosystems

Question 4

What are the two types of Photosystems

Answer 4

Photosystem I and Photosystem II

Question 5

These are light harvesting complex made up of 250-400 pigment molecules, accessory pigments and associated proteins.

Answer 5

Photosystems

Question 6

Where can photosystems be found?

Answer 6

Thylakoid membrane

Question 7

To be more specific, where can the photosystems be found on plants and algae?

Answer 7

The thylakoid membrane of the chloroplast

Question 8

To be more specific, where can the photosystems be found on photosynthetic bacterias?

Answer 8

Cell membrane of photosynthetic bacterias

Question 9

What are the two functions of photosystems?

Answer 9

-Absorbing light energy
- Transfer of energy and electrons

Question 10

This is the site of dependent reactions

Answer 10

Thylakoid membrane

Question 11

The enzyme NADP reductase then transfers electrons from ferredoxin to NADP+, generating what?

Answer 11

NADPH

Question 12

Each photosystem consists of two closely linked components, what are these?

Answer 12

• Reaction Centre
• Antenna Molecules

Question 13

This type of photosystem have maximum absorption at 700nm or far red region or photocentre is P700
-Pigments absorbs long wavelengths of light

Answer 13

Photosystem I

Question 14

This type of photosysyem has an iron-sulphur (FeS) type reaction centre

Answer 14

Photosystem 1

Question 15

This type of photosystem is rich in chlorophyll-a

Answer 15

Photosystem I

Question 16

This type of photosystem does not act as a proton pump; instead, it uses these high-energy electrons to reduce NADP+ to NADPH.

Answer 16

Photosystem I

Question 17

What are used to produce ATP?

Answer 17

Hydrogen ions

Question 18

This type of photosystem have maximum absorption at 680 nm or red region or photocentre is 680

Answer 18

Photosystem II

Question 19

This type of photosystem have pigments that absorbs shorter wavelengths of light

Answer 19

Photosystem II

Question 20

This type of photosystem is rich in chlorophyll-b

Answer 20

Photosystem II

Question 21

What are the two possible ways for electron flow

Answer 21

Cyclic and Non-cyclic phosphorylation

Question 22

In this way of electron flow, only PS I is involved

Answer 22

Cyclic phosphorylation

Question 23

It is a process which results in the movement of electrons in a cyclic manner to produce ATP.

Answer 23

Cyclic phosphorylation

Question 24

This way of electron flow happens in the thylakoid membrane which uses photosystem I and the chlorophyll P700.

Answer 24

Cyclic phosphorylation

Question 25

When light is absorbed in PS I, where does the excited electrons enter to produce ATP from ADT + Pi?

Answer 25

Electron Transport Chain

Question 26

What happens to the excited electrons as it enters the Electron Transport Chain?

Answer 26

It loses its energy

Question 27

when the electron loses its energy as it enters the Electron Transport Chain, where does it go to restore its energy?

Answer 27

Photosystem I

Question 28

In this way of Electron flow, PS I and PS II are involved

Answer 28

Non-cyclic Phosphorylation

Question 29

In this way of electron flow, ATP is produced that will be used as energy needed for the Calvin cycle.

Answer 29

Non-cyclic Phosphorylation

Question 30

Why is it called Non-cyclic Phosphorylation?

Answer 30

because, the loss of electrons in P680 in photosystem II are occupied by P700 in photosystem I and are not returned to P680.