The Average Life Span in the Twentieth Century

question 48

Multiple Choice

The average life span in the twentieth century

• A)did not change significantly.
• B)increased slightly.
• C)nearly doubled.
• D)nearly tripled.

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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.