How Many Chromosomes Are Found in Human Body Cells?
- Chromosomes are comprised of DNA (deoxyribonucleic acid), genetic material that determines individual characteristics. The cell's nucleus primarily contains chromosomes, in addition to the nucleolus and protein particles, that are organized in pairs of sequences that replicate (duplicate) during cellular reproduction.
- Humans have 46 chromosomes, or 23 pairs of chromosomes in the cell nucleus. The DNA sequence in each chromosome comes from one parent and the chromosomal sequence directs the functions and characteristics of the body cells.
- Cells in the body are called somatic cells, which organize to form tissues and organs responsible for specialized functions (determined by the chromosomes). The human body maintains regular repair and regeneration of tissues through cellular division (reproduction and proliferation).
- A red blood cell is produced in the bone marrow and when it matures in mammals, it loses its nucleus for space to carry hemoglobin, which is responsible for transporting oxygen to cells. Red blood cells live for about 120 days before being broken down by the body; essential products such as iron are transferred back into the circulation system.
- Sex cells are produced in the ovaries in women and testes in men and contain only half the number of chromosomes (23). The sex cells are produced through meiosis, a process which adds another step to the cell reproduction cycle so that the chromosome pairs are split, enabling sex cells to combine later during fertilization.
