A gene is best defined as Select one:. a) a sequence of nucleotides in DNA that codes for a functional product. b) a transcribed unit of DNA. three nucleotides that code for an amino acid. c) a sequence of nucleotides in RNA that codes for a functional product. d) a segment of DNA.

a) a sequence of nucleotides in DNA that codes for a functional product

Explanation: A gene is a segment of a DNA molecule that contains the information required for the synthesis of a functional biological product, whether a protein or RNA.

Genes are transcribed into an mRNA in the process of transcription which is then used for the synthesis of a protein. Not all segments of DNA code for the amino acid sequence of a polypeptide. The coding regions are called the genes while the non-coding regions are called the introns or intervening segments.

"it built up in the atmosphere"

i think thats it, idk, i tried looking for this exact q& a for grad. and idk if i got this question right or sorry if im wrong