JAMB - Biology (2005 - No. 44)
Which of the following is the best explanation for a child who is phenotypically short and born of two tall parents
The father possesses a gene for shortness
The mother posesses a gene for shortness
Nature makes the child short
Both parents possess gene for shortness
Giải thích
Two tall parents can have a phenotypically short child if both parents carry a recessive gene for shortness, even though they themselves are tall, and the child inherits two copies of that recessive gene, one from each parent.
While genetics play a significant role in determining height, it's not controlled by a single gene, but rather by multiple genes and their interactions. If we use the letters "T" for tall and "t" for short, the parents would be "Tt". The child could have TT (tall), Tt (tall), tT (tall) or tt (short).
Kindly note that although genetics are a major factor, other factors like nutrition, hormones, and medical conditions can also influence a child's height.