What term refers to cells that have one copy of each chromosome?

• A. Diploid
• B. Haploid
• C. Monoploid
• D. Chromatid

Answer: (B)

The term that refers to cells with one copy of each chromosome is "haploid." Haploid cells contain half the number of chromosomes compared to diploid cells. In humans, for instance, haploid cells are the gametes—sperm and eggs—which carry one set of chromosomes (23 in humans) that fuse during fertilization to form a diploid zygote with two sets of chromosomes (46 total).

Diploid cells, on the other hand, are characterized by having two copies of each chromosome, one inherited from each parent. Monoploid is often used in a similar context but can have different meanings in various species, whereas chromatid refers to one half of a duplicated chromosome and is not a term that describes the overall chromosome number in a cell. Understanding the distinction between these terms is crucial in genetics, particularly when studying processes like meiosis and the formation of gametes.