The term for a cell containing a single set of chromosomes and genes is?

The term for a cell containing a single set of chromosomes and genes is?

• A. Haploid
• B. Diploid
• C. Polyploid
• D. Tetraploid

Answer: (A)

Ploidy refers to the number of chromosome sets in a cell. A cell with a single set of chromosomes and genes is haploid, meaning it has one complete set of chromosomes (N). In humans, for example, gametes are haploid with 23 chromosomes, produced by meiosis so that fertilization restores the diploid number in the zygote. By contrast, a cell with two sets is diploid (2N), which is typical for most body cells. A polyploid cell has more than two sets, with tetraploid constituting four sets. So the description of having a single set directly defines haploid.

Ploidy refers to the number of chromosome sets in a cell. A cell with a single set of chromosomes and genes is haploid, meaning it has one complete set of chromosomes (N). In humans, for example, gametes are haploid with 23 chromosomes, produced by meiosis so that fertilization restores the diploid number in the zygote. By contrast, a cell with two sets is diploid (2N), which is typical for most body cells. A polyploid cell has more than two sets, with tetraploid constituting four sets. So the description of having a single set directly defines haploid.