How many chromosomes does a male field mouse have if the female has 40? - briefly
A male field mouse has 40 chromosomes in total, the same number as the female. The difference lies only in the sex chromosomes (XY in males versus XX in females).
How many chromosomes does a male field mouse have if the female has 40? - in detail
The female of the species possesses 40 chromosomes; the male carries the identical diploid number. In this rodent, the complement consists of 38 autosomes and a pair of sex chromosomes. The female’s sex chromosomes are two X chromosomes (XX), while the male’s are one X and one Y (XY). Because the autosomal set is unchanged between sexes, the total chromosome count remains 40 for both.
Key points:
- Diploid number: 40 chromosomes in both sexes.
- Autosomes: 38 chromosomes (19 pairs).
- Sex chromosomes: female = XX, male = XY.
- The Y chromosome is morphologically smaller than the X but contributes to the same total count.
- Karyotypic analysis using G‑banding or fluorescent in situ hybridization confirms the identical chromosome number across sexes in field mice.
Thus, a male field mouse has 40 chromosomes, matching the female’s complement, with the distinction residing only in the composition of the sex‑chromosome pair.