How many chromosomes does a somatic cell of a mouse contain? - briefly
A mouse somatic cell contains 40 chromosomes, organized as 20 homologous pairs. This diploid number is characteristic of Mus musculus.
How many chromosomes does a somatic cell of a mouse contain? - in detail
A mouse somatic cell is diploid, containing 40 chromosomes organized into 20 homologous pairs. Each pair consists of one chromosome inherited from the mother and one from the father. The diploid number (2n) therefore equals 40, while the haploid number (n) found in gametes is 20.
The chromosome complement includes:
- 22 autosomes arranged in 11 pairs; - 2 sex chromosomes, forming either an XX (female) or XY (male) configuration.
Each chromosome possesses a centromere, short (p) and long (q) arms, and characteristic banding patterns that facilitate identification under microscopy. Mouse chromosomes are metacentric to submetacentric, differing in size and morphology from human chromosomes, which have a diploid number of 46.
During the cell cycle, the 40 chromosomes replicate in the S phase, producing sister chromatids that remain attached at the centromere until segregation in mitosis. This ensures that each daughter cell inherits an identical set of 40 chromosomes.
Comparative genomics indicates that the mouse genome, although smaller in chromosome count, shares extensive homology with the human genome, allowing mouse models to serve as valuable tools in biomedical research.