NEET2026BiologyChapterActual
According to the chromosomal basis of sex determination, which of the following statements accurately describes the gametes produced by a male in the XX-XO system?
Options
- A50% of the sperms carry an X chromosome and 50% carry a Y chromosome.
- B100% of the sperms carry a single X chromosome.
- C50% of the sperms carry an X chromosome and 50% lack any sex chromosome.
- D50% of the sperms carry a Z chromosome and 50% carry a W chromosome.
Correct answer
C. 50% of the sperms carry an X chromosome and 50% lack any sex chromosome.
Step-by-step solution
In the XX-XO type of sex determination, females are homogametic (XX) and males are heterogametic (XO). Males possess only one X chromosome besides the autosomes. During spermatogenesis, 50% of the sperms receive the X chromosome, while the remaining 50% do not receive any sex chromosome. Therefore, 50% of the sperms carry an X chromosome and 50% lack any sex chromosome. Answer: 50% of the sperms carry an X chromosome and 50% lack any sex chromosome.