Final answer:
The correct order from the smallest to the largest element of genetics is nucleotide, gene, DNA, chromosome. Nucleotides make up genes, genes are segments of DNA, and DNA is organized into chromosomes.
Step-by-step explanation:
The correct progression from larger to smaller elements of our genetics, from the options provided, is B. Chromosome->DNA->Gene->Nucleotide. The structural hierarchy of genetic material starts with the chromosome, which is a long strand of DNA that is coiled and condensed. Within a chromosome, there is DNA (deoxyribonucleic acid), which is the molecule that carries the genetic instructions. A gene is a segment of DNA that contains coding for a protein or a function. The nucleotides are the subunits of DNA and RNA, comprising a nitrogenous base, a sugar, and a phosphate group. In order of increasing complexity, the correct sequence is nucleotide (a single building block of DNA and RNA), gene (a sequence of nucleotides coding for a protein), DNA (long strands of genes), and chromosome (the complete structure that organizes and carries DNA).
To further clarify, other genetic elements ranked from smallest to largest include a base pair (a pair of complementary nitrogenous bases in DNA linked by hydrogen bonds: adenine (A) with thymine (T), and cytosine (C) with guanine (G)), a codon (a sequence of three nucleotides that corresponds to a specific amino acid or stop signal during protein synthesis), and chromatin (a complex of DNA and protein found in eukaryotic cells that packages DNA into a smaller volume to fit in the cell).