Chloroplasts And Chlorohyll

Question 1

What are photosynthetic pigments

Answer 1

Absorb certain wavelengths of light
Reflect other wavelengths (the colours we see)
Arranged in photosystems in thylakoid membranes

Question 2

Where is chlorophyll A

Answer 2

In the primary pigment centre

Question 3

What two forms of light are absorbed by chlorophyll A and what colour do the absorb/appear

Answer 3

p680 photosystem 2
P700 photosystem 1
Appears yellow green
Absorbs red (or blue at 450nm)

Question 4

What are the two types of accessory pigments

Answer 4

Chlorophyll B

Carotenoids

Question 5

What wavelength does chlorophyll B appear and what colour does it appear

Answer 5

Absorbs 500-640nm

Appears blue green

Question 6

What colour do carotenoids absorb/appear

Answer 6

Absorbs blue light
Appears yellow (xanthophyll) or orange (carotene) 
They absorb light not normally absorbed by chlorophyll and pass them to reaction centres

Question 7

What happens to electrons lost by accessory pigments

Answer 7

They are passed to chlorophyll A to replace the electrons they lost

Question 8

How are leaves adapted to take in the most amount of light

Answer 8

LARGE VACUOLE so chloroplasts do not shade each other
THYLAKOIDS maximise absorption
SPACES IN SPONGY MESOPHYLL to maximise surface area for gas exchange
LARGE SURFACE AREA AND THIN
COLUMN SHAPED PALISADE CELLS less walls to travel through so less light deflected and more chloroplasts reached

Question 9

What is a photosystem

Answer 9

Clusters of hundreds of photosynthetic pigments that collect light energy and pass it to the special chlorophyll at the reaction centre

Question 10

Where do electrons passed to chlorophyll A go to

Answer 10

Primary electron acceptor