NEET BIOLOGY

Detailed explanation-1: -The first fossils of prokaryotic (bacterial) cells are known from 3.5 and 3.4 billion years ago. These bacteria were photosynthetic (although non-oxygen producing) so it is likely that simpler non-photosynthetic bacteria evolved prior to this (Schopf, 1987; Beukes, 2004).

Detailed explanation-2: -The eukaryotes developed at least 2.7 billion years ago, following some 1 to 1.5 billion years of prokaryotic evolution.

Detailed explanation-3: -Prokaryotes are the most primitive of cells (meaning they are the oldest and simplest), and they lived at least 3.5 billion years ago. For nearly 2 billion years, prokaryotes were the only organisms on Earth. The most familiar example of prokaryotes is bacteria.

Detailed explanation-4: -The first cells were most likely primitive prokaryotic-like cells, even more simplistic than these E. coli bacteria. The first cells were probably no more than organic compounds, such as a simplistic RNA, surrounded by a membrane.

Detailed explanation-5: -Lacking a nucleus and organelles, prokaryotic organisms are thought to be some of the oldest life forms on the planet. Archaea can be found in places where other life would not survive.