In human somatic cells, how many chromosomes are present?

• A. 23
• B. 46
• C. 92
• D. 44

Answer: (B)

Human somatic cells contain a total of 46 chromosomes, which consist of 23 pairs. These chromosomes are organized into homologous pairs, with one chromosome of each pair inherited from each parent. The first 22 pairs are called autosomes, while the 23rd pair consists of the sex chromosomes (XX for females and XY for males). This diploid number (2n = 46) is characteristic of most somatic cells in the human body, as opposed to gametes (sperm and egg cells), which contain only 23 chromosomes (haploid number, n = 23) to ensure that when fertilization occurs, the resulting zygote has the correct diploid number. Understanding this chromosomal makeup is crucial for grasping concepts such as inheritance, genetic diversity, and various genetic disorders.