Which statement defines a haploid cell?

Which statement defines a haploid cell?

• A. A cell with two sets of chromosomes
• B. A cell with multiple copies of chromosomes
• C. A cell with half the number of chromosomes relative to a somatic cell
• D. A cell with one set of chromosomes

Answer: (D)

A haploid cell contains a single complete set of chromosomes—that is, one copy of each chromosome (in humans, 23 chromosomes). This is what distinguishes haploid from diploid cells, which carry two sets (2n) of chromosomes, like most body (somatic) cells that have 46 in humans. Haploid cells are produced by meiosis in germ cells, and when two haploid gametes fuse during fertilization, the resulting zygote has two sets again. Saying a cell has one set directly captures the defining idea of haploidy. Saying it has half the number relative to a somatic cell conveys the same idea in numbers (one genome vs. two genomes in humans), but the clearest, most precise definition is having one complete set of chromosomes. The other statements describe diploidy (two sets) or polyploid/duplicated content (multiple copies), which do not define haploid.

A haploid cell contains a single complete set of chromosomes—that is, one copy of each chromosome (in humans, 23 chromosomes). This is what distinguishes haploid from diploid cells, which carry two sets (2n) of chromosomes, like most body (somatic) cells that have 46 in humans. Haploid cells are produced by meiosis in germ cells, and when two haploid gametes fuse during fertilization, the resulting zygote has two sets again.

Saying a cell has one set directly captures the defining idea of haploidy. Saying it has half the number relative to a somatic cell conveys the same idea in numbers (one genome vs. two genomes in humans), but the clearest, most precise definition is having one complete set of chromosomes. The other statements describe diploidy (two sets) or polyploid/duplicated content (multiple copies), which do not define haploid.