Final answer:
The order from smallest to largest is nitrogen base, nucleotide, codon, gene, and chromosome. A human genome contains pairs of chromosomes with many genes, which are organized into a precise structure that fits within the cell nucleus.
Step-by-step explanation:
The order of chromosomes, genes, and DNA components from smallest to largest is as follows:
- Nitrogen base (A single chemical unit that is part of the DNA structure)
- Nucleotide (A combination of a nitrogen base, a sugar molecule, and a phosphate group that forms the basic structural unit of DNA)
- Codon (A sequence of three nucleotides which together form a unit of genetic code in a DNA or RNA molecule)
- Gene (A section of DNA that contains the instructions for developing one or more proteins, found within chromosomes)
- Chromosome (A long continuous thread of DNA that contains many genes, regulatory elements, and other nucleotide sequences)
Each human genome contains 23 pairs of chromosomes, with hundreds to thousands of genes on each of these chromosomes. These chromosomes are packaged with proteins to fit within the cell nucleus.