Haploid refers to how many sets of chromosomes?

• A. Two sets
• B. One set
• C. Three sets
• D. No chromosomes

Answer: (B)

Haploid refers to having one complete set of chromosomes. This means one copy of each chromosome, often written as n. In contrast, diploid organisms have two sets (2n), which is why most human body cells carry two copies of each chromosome. Gametes—sperm and egg—are haploid so that when fertilization occurs, the resulting zygote has the normal two sets. For the specific question, the correct idea is that haploid means one set. Two sets would be diploid, three sets would be triploid, and having no chromosomes would leave no genetic material at all.