Why are the reaction centers of photosystems composed of several structurally different pigments?

Explanation:

Photosystems are structural and functional

units of protein complexes that are involved in photosynthesis and carry out the absorption of light and transfer of electrons and energy. The reaction centers of photosystems are made up of structurally different pigments which enables plants absorb light energy at different wavelengths.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.