AP BIOLOGY

Detailed explanation-1: -Prokaryotes are underdeveloped cells, undifferentiated organelles with no nuclei. They have circular DNA. It suggests that prokaryotes evolved first while eukaryotes have well defined membrane bound nucleus and cell organelles. The first organisms to evolve on earth were bacteria.

Detailed explanation-2: -Prokaryotes were the earliest life forms, simple creatures that fed on carbon compounds that were accumulating in Earth’s early oceans. Slowly, other organisms evolved that used the Sun’s energy, along with compounds such as sulfides, to generate their own energy.

Detailed explanation-3: -The earliest life forms we know of were microscopic organisms (microbes) that left signals of their presence in rocks about 3.7 billion years old. The signals consisted of a type of carbon molecule that is produced by living things.

Detailed explanation-4: -The eukaryotes developed at least 2.7 billion years ago, following some 1 to 1.5 billion years of prokaryotic evolution.

Detailed explanation-5: -The first fossils of prokaryotic (bacterial) cells are known from 3.5 and 3.4 billion years ago.