Which term describes an organism or cell having only one complete set of chromosomes?

Which term describes an organism or cell having only one complete set of chromosomes?

• A. Geographical Isolation
• B. Gamete
• C. Diploid Cell
• D. Haploid

Answer: (D)

Ploidy describes how many complete chromosome sets are in a cell. Having only one complete set means the genome is haploid: there is just one copy of each chromosome. In humans, a haploid cell carries 23 chromosomes, while most body (somatic) cells are diploid with two copies of each chromosome, totaling 46. The term haploid is especially relevant for gametes, the reproductive cells produced by meiosis; when two haploid gametes fuse during fertilization, the organism restores two chromosome sets. A gamete is a haploid cell, but the word that describes having one complete set is haploid. Other concepts, like geographical isolation, aren’t about chromosome numbers.

Ploidy describes how many complete chromosome sets are in a cell. Having only one complete set means the genome is haploid: there is just one copy of each chromosome. In humans, a haploid cell carries 23 chromosomes, while most body (somatic) cells are diploid with two copies of each chromosome, totaling 46. The term haploid is especially relevant for gametes, the reproductive cells produced by meiosis; when two haploid gametes fuse during fertilization, the organism restores two chromosome sets. A gamete is a haploid cell, but the word that describes having one complete set is haploid. Other concepts, like geographical isolation, aren’t about chromosome numbers.