Answer:
organism, organ system, organ, tissue, cell
Explanation:
Answer: allele, gene, DNA, chromosome, nucleus
Explanation: An allele is a variant of a gene or a different form of a gene. A gene is a segment of a DNA that codes for an RNA or a protein. A DNA is a genetic material that contains all the genetic information of an organism. A DNA is packaged and condensed into a threadlike material known as chromosome and chromosomes are found in the nucleus of a cell.
