pigment extraction

chloroplast are photo pigments, if you want to see how the water molecules are split inside the thylakoid space, how many membranes would you have to cross to get there?

3

what is wrong with the centrifuge set up

it is not balanced

where are the pigment molecules located

In a protein complex that keeps them in place

the chloroplasts are suspended in an isolation buffer. to be able to extract the pigments from the chloroplasts, we have to get rid of the buffer first. whats the best way to separate the chloroplasts from the buffer

Use a centrifuge to separate the chloroplasts

what kind of pigment is this

chlorophyll

why do pigments absorb visible light and other molecules dont

extended conjugated systems

what color is not absorbed by this pigment (hexane)

green

what color of light does this pigment absorb (water)

green

we are about to dissolve the chloroplasts in hexane and water l. hexane is a very hydrophobic solvent. hence, it will elute the hydrophobic chlorophyll molecules. the dar colors suggests that there must be at least one other pigment that absorbs the green light. where do you expect to find this unknown pigment?

hydrophobic??

Do the results support your alternative hypothesis? that red pigment is hydrophobic

no the unknown pigment is water soluble

what is photosynthesis

the process used by organisms to convert light energy to chemical energy

perfect! now we have to use a solvent to elute the pigment. to elute all the pigments contained in the chloroplast, what do you have to consider, when choosing from different solvents?

use both hydrophobic and hydrophilic solvent