Emergence Of Photosynthesis

The first single-celled organisms were heterotrophs; they could not manufacture their own food. These organisms consumed the inorganically formed amino acids or other chemicals existing in their immediate environment. These early organisms received energy from these amino acids by fermentation, the processes of breaking down food molecules (sugars) through a series of chemical steps, into carbon dioxide and alcohol. When photosynthesis began, organisms became able to manufacture their own food from inorganic elements, and they became auto-trophs, typically following the reaction

Photosynthesizing organisms thus produced food for other heterotrophs and also released oxygen into the atmosphere. The exact timing of when organisms became able to produce chlorophyll is unknown, but the oldest record of chlorophyll is found in 3.5 billion-year-old stromatolites from Australia.

Continue reading here: Life In The Precambrian

Was this article helpful?

0 0