Which of the following describes a haploid cell?

A haploid cell is defined as a cell that contains one complete set of chromosomes. In humans, for example, haploid cells are found in gametes—sperm and egg cells—which each contain 23 chromosomes, as opposed to the diploid cells which have two sets of 23 chromosomes, totaling 46.

The concept of haploidy is crucial in the context of sexual reproduction, as it allows for the combination of genetic material from two parents to form a diploid zygote during fertilization. When the sperm and egg fuse, their respective haploid sets combine to restore the diploid state in the resulting zygote.

Understanding this definition helps clarify why the option indicating a cell with two sets of chromosomes refers to diploid cells, not haploid. The option suggesting a cell containing no chromosomes is inaccurate, as all viable cells need chromosomes to perform essential functions. Lastly, a cell with multiple sets of chromosomes refers to polyploidy, which is a different classification entirely. Thus, the correct description of a haploid cell is one that contains a single set of chromosomes.