But an onion isn’t very complex either, and it has more than 12 times as much DNA as a Harvard professor. After all, DNA is the stuff of which genes are made, and genes contain recipes for making proteins that make humans, amoebas, and onions what they are.

Even bananas surprisingly still share about 60% of the same DNA as humans!

The tiny water flea Daphnia has the most genes of any animal, some 31,000. Scientists have discovered that the animal with the most genes–about 31,000–is the near-microscopic freshwater crustacean Daphnia pulex, or water flea. By comparison, humans have about 23,000 genes.

Since the onion (Allium cepa) is a diploid organism having a haploid genome size of 15.9 Gb, it has 4.9x as much DNA as does a human genome (3.2 Gb).

Australian lungfish

The flower, Paris japonica, has an astonishing 50 times more DNA than humans.

1282 left column 2nd paragraph:”At 13,033,799 base pairs, the circular chromosome is the largest bacterial genome described to date by ~4 Mb. The S. cellulosum genome contains 9,367 predicted protein coding sequences (CDS), numbered from the initiation codon of the dnaA gene.”

With 150 billion base pairs of DNA per cell (50 times larger than that of a human haploid genome), Paris japonica may possess the largest known genome of any living organism; the DNA from a single cell stretched out end-to-end would be longer than 300 feet (91 m).

They can study these preserved genes and compare the genomes of different species to uncover similarities and differences that improve their understanding of how human genes function and are controlled. This knowledge helps researchers develop new strategies to treat and prevent human disease.

Paris japonica, the rare Japanese flower that holds the current record for largest genome at 149 billion nucleotides….Table 1.

Our genetic manual holds the instructions for the proteins that make up and power our bodies. But less than 2 percent of our DNA actually codes for them. The rest — 98.5 percent of DNA sequences — is so-called “junk DNA” that scientists long thought useless.

But while size matters for biodiversity studies and understanding the evolution of such large genomes, bigger doesn’t necessarily mean more complex. A larger genome size may simply be indicative of repetitive DNA, rather than a greater number of genes that actually contribute to the organisms’ code.

C-value is the amount, in picograms, of DNA contained within a haploid nucleus (e.g. a gamete) or one half the amount in a diploid somatic cell of a eukaryotic organism.

Single-celled amoebae have some of the largest genomes, up to 100-fold larger than the human genome. This variation suggested that genomes can contain a substantial fraction of DNA other than for genes and their regulatory sequences. C.A. Thomas Jr dubbed it the ‘C-value paradox’ in 1971.

The haploid number (n) refers to the total number of chromosomes found in a gamete (a sperm or egg cell produced by meiosis in preparation for sexual reproduction).

The “n” can be viewed as the number of homologous pairs of chromosomes; however, a more precise definition would be that “n” is the number of homologous pairs of gene loci on all chromosomes present in the cell.

Ploidy is a term referring to the number of sets of chromosomes. Haploid organisms/cells have only one set of chromosomes, abbreviated as n.

Crossing over produces two chromosomes that have not previously existed. The process of recombination involves the breakage and rejoining of parental chromosomes (M, F). This results in the generation of novel chromosomes (C1, C2) that share DNA from both parents.