Are all unicellular organisms haploid? If not, how do we know a cell is haploid or diploid?

Haploid number refers to a set of chromosomes that differ from one another in morphology and the genes present on these. All chromosomes in haploid cells are different in appearance as far as the length and position of centromere is concerned.

A diploid cell has a complete set of chromosomes, each of which is present in duplicate. Two chromosomes in a diploid cell are identical to one another in terms of length and centromere position. Genes found on two chromosomes on identical loci represent the same character, but they may carry different alleles of the same gene. These two chromosomes are known as homologous chromosomes.

As a result, it is simple to determine whether a given cell is diploid or haploid: a cell is diploid if every chromosome has a visible homologous or duplicate chromosome, and haploid if every chromosome differs from the other in morphology.

Not all unicellular organisms are haploid. Some unicellular organisms can be diploid, meaning they have two sets of chromosomes. To determine whether a cell is haploid or diploid, scientists can use techniques such as chromosome counting or examining the stages of cell division (like mitosis or meiosis). Additionally, genetic analysis can help identify the number of chromosome sets present in a cell.