AP BIOLOGY

Detailed explanation-1: -These microbes possessed the remarkable ability to perform photosynthesis, (i.e., they could generate energy from sunlight). Cyanobacteria possessed the machinery to utilize water as a fuel source by oxidizing it. More significantly, the by-product of photosynthesis happened to be oxygen.

Detailed explanation-2: -Cyanobacteria, also called blue-green algae, were among the earliest organisms on Earth. These primitive bacteria produce oxygen during photosynthesis as they fix CO2 dissolved in the water.

Detailed explanation-3: -The result is that lab-grown cyanobacteria will produce oxygen but to no more than 10% of our present levels-exactly the amount of oxygen produced in the Proterozoic.

Detailed explanation-4: -"Cyanobacteria are the very first organisms that figured out how to make oxygen. How to take water, which is really abundant everywhere on Earth, and, using sunlight, split its molecules to make oxygen, ” says Bosak.

Detailed explanation-5: -And some evidence suggests cyanobacteria, the earliest photosynthetic organisms to release oxygen gas as a waste product-although not use it-may have arisen as early as 3.5 billion years ago.