Question

Life was first formed in

• A. The oceans of primitive earth
• B. The freshwaters of primitive earth
• C. The primordial atmosphere of the earth
• D. The primordial lithosphere of the earth

Answer 1

The correct option is A

The oceans of primitive earth

Earth was formed approximately 4.5 billion years ago. As it cooled down, a primitive atmosphere was created by the outgassing of early volcanoes. The early atmosphere contained no oxygen and could not support most of the life forms. some of the chemicals viz., hydrogen, helium, carbon dioxide, nitrogen etc. were gradually converted to simple organic molecules and then into complex organic molecules like DNA and RNA. These chemical reactions made the ocean a reservoir of chemicals. Hence, it was known as the “organic soup”. Progressively, self-replication of simple nucleic acid molecules led to the origin of various simple life forms on Earth.