During the light reactions of photosynthesis, why is a molecule of water split? to provide energy for the electron transport chain
a.) to provide energy for the electron transport chain
b.) to produce electrons that replace the two electrons that were lost from the chlorophyll molecule
c.) to assist in the process that produces ATP
d.) to form NADPH

B

Explanation:

Electrons from photosystem II go through the ECT in the chloroplast, so water is split to replace those electrons.

the nitrogen cycle provides nitrogen to the ecosystem from the atmosphere, ground and oceans. nitrogen is an important component of complex molecules such as amino acids and nucleotides, which lead to the creation of proteins and dna, the building blocks of all life. plants absorb nitrogen in the form of ammonium, nitrate ion and, on rare occasions, as amino acids. animals receive nitrogen necessary for biological processes from feeding on living or dead organic matter.