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(biochemistry) a nucleoside that is a structural component of nucleic acids; it is present in all living cells in a combined form as a constituent of DNA and RNA and ADP and ATP and AMP

(biochemistry) a nucleoside that is a structural component of nucleic acids; it is present in all living cells in a combined form as a constituent of DNA and RNA and ADP and ATP and AMP

A nucleoside that is composed of adenine and d-ribose. Adenosine or adenosine derivatives play many important biological roles in addition to being components of DNA and RNA. Adenosine itself is a neurotransmitter.