MCQ Detailed View

In humans, the Y chromosome is one of the two sex chromosomes and determines male sex characteristics. Humans have 23 pairs of chromosomes, including one pair of sex chromosomes: XX in females and XY in males. The Y chromosome is passed exclusively from father to son, because only males carry this chromosome. Mothers do not possess a Y chromosome and therefore cannot contribute it to their offspring.

During fertilization, a sperm cell carrying either an X or Y chromosome fuses with the mother’s X-bearing egg. If the sperm contributes a Y chromosome, the resulting zygote will be male (XY). If it contributes an X chromosome, the zygote will be female (XX). This mechanism explains why the Y chromosome is always transmitted along the paternal line.

The Y chromosome carries genes critical for male development, including the SRY gene, which triggers the formation of testes and the development of male reproductive structures. Because it is only present in males, the Y chromosome is also useful in tracing paternal ancestry and lineage through generations.

Other options in the question are incorrect:

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  Mothers can only pass an X chromosome to their children.

  
  


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  Fathers pass the X chromosome to daughters, but only sons receive the Y chromosome.

  
  


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  Therefore, the correct answer is Father to son.

  
  

Understanding Y chromosome inheritance is a fundamental concept in genetics, human biology, and reproductive science. It explains sex determination, inheritance patterns, and the biological basis of male lineage tracing in genetics. This knowledge is essential for students learning about chromosomal biology, heredity, and human reproduction.