polyploid cell

Polyploid cells and organisms are those containing more than two paired (homologous) sets of chromosomes.

The embryo, larva and stolon are surrounded by a protective polyploid cell, which also functions in digestion.

Polyploid cells have multiple copies of chromosomes and haploid cells have single copies.

Diploid liver cells express high levels of H19, whereas the polyploid cell fraction do not express H19.

Counterintuitively, inhibition of Aurora B kinase actually causes the polyploid cells formed to continue dividing however, because these cells have severe chromosomal abnormalities, they eventually stop dividing or undergo cell death.

This is because the fitness cost (survival to next generation) of chromosomal instability is lower in polyploid cells, as the cell has a greater number of chromosomes to make up for the chromosomal instability it experiences.

Usually, haploidisation creates a monoploid cell from a diploid progenitor, or it can involve halving of a polyploid cell, for example to make a diploid potato plant from a tetraploid lineage of potato plants.

In fact, Dr. Bhaskaron, who conducted the experiment on five children suffering from kwashiorkor, a severe form of protein-calorie malnutrition, noted in his published paper that the biological significance of the formation of polyploid cells - the chromosomal damage - was unclear, as was their long-term significance.

Diploid and polyploid cells whose chromosomes have the same allele of a given gene at some locus are called homozygous with respect to that gene, while those that have different alleles of a given gene at a locus, are called heterozygous with respect to that gene.