What term describes a cell with chromosomes in an exact multiple of the haploid number, normally two in humans?

What term describes a cell with chromosomes in an exact multiple of the haploid number, normally two in humans?

• A. Aneuploidy
• B. Euploidy
• C. Monoploidy
• D. Haploidy

Answer: (B)

The concept being tested is euploidy. Euploidy means the chromosome number is an exact multiple of the haploid set. In humans, the haploid number is 23, so cells with two complete sets (46 chromosomes) are diploid and euploid, as are cells with 69 or 92 chromosomes (triploid or tetraploid)—any whole-number multiple of 23. This contrasts with aneuploidy, where the chromosome count is not a simple multiple of the haploid number (for example, a missing or extra chromosome like monosomy or trisomy). Haploidy refers to a single set (n), not multiples, and monoploidy is a less common term for that single-set state.

The concept being tested is euploidy. Euploidy means the chromosome number is an exact multiple of the haploid set. In humans, the haploid number is 23, so cells with two complete sets (46 chromosomes) are diploid and euploid, as are cells with 69 or 92 chromosomes (triploid or tetraploid)—any whole-number multiple of 23. This contrasts with aneuploidy, where the chromosome count is not a simple multiple of the haploid number (for example, a missing or extra chromosome like monosomy or trisomy). Haploidy refers to a single set (n), not multiples, and monoploidy is a less common term for that single-set state.