A human cheek cell, like most other human somatic cells, contains 46 chromosomes. These are organized into 23 pairs: 22 pairs of autosomes (non-sex chromosomes) and one pair of sex chromosomes (XX for females, XY for males).
Understanding Chromosomes and Cheek Cells
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Chromosomes: These are thread-like structures located inside the nucleus of animal and plant cells. They carry the genetic information in the form of DNA, which dictates the characteristics and functions of an organism.
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Somatic Cells: These are all the cells in the body except for the reproductive cells (sperm and egg). Somatic cells are diploid, meaning they have two sets of chromosomes – one inherited from each parent.
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Cheek Cells (Buccal Cells): These are easily accessible cells lining the inside of the mouth. They are commonly used in genetic testing because they are readily collected through a simple cheek swab. Since they are somatic cells, they contain the typical number of chromosomes found in most human cells.
Exceptions
While the standard number of chromosomes in a human cell is 46, there are exceptions:
- Gametes (sex cells): Sperm and egg cells have only 23 chromosomes (haploid), one from each chromosome pair. This is so that when they fuse during fertilization, the resulting zygote will have the correct diploid number of 46.
- Chromosomal Abnormalities: Genetic disorders can result in cells having an abnormal number of chromosomes (e.g., Down syndrome, Turner syndrome). These abnormalities can affect various cell types, including cheek cells. However, the standard number in a healthy individual is 46.
Several sources confirm this information:
- Mount Sinai: "Normally, each cell in the human body has 23 pairs of chromosomes (46 total chromosomes)."
- Brainly: "A human cheek cell, like most other human, contains 46 chromosomes."
- Answers.com: "46 chromosomes. The only cells in the human body that do not contain 46 chromosomes are specialist cells which have no cell nucleus (e.g., a red blood cell)."
