Microbial Life Appeared on This Planet as Early As

question 13

Multiple Choice

Microbial life appeared on this planet as early as:

• A) 10.4 billion years ago
• B) 3.8 billion years ago
• C) 1.2 billion years ago
• D) 58 million years ago
• E) 29 million years ago

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Definitions:

RNA

Ribonucleic acid is a type of nucleic acid found in every living cell, serving as a messenger that transports directions from DNA for the production of proteins.

Nitrogen Bases

Organic molecules that make up the building blocks of DNA and RNA, including adenine, thymine, cytosine, guanine, and uracil.

Enzymes

Natural substances that markedly enhance the rate at which virtually all intra-cellular chemical reactions occur.

Catalysts

Substances that speed up chemical reactions without being consumed or altered in the process, critical in facilitating various biological and industrial processes.