Answer:
This trait is rare when it occurs. Some genes depend on other genes to be expressed, so in most cases a trait is denied an expression. But its still there, so it passes down to generation until it gets expressed.
Explanation:
Answer:
Because it's a recessive trait
Explanation:
There are two chromosomes that determine your biological sex: XX for the female and XY for the male. You inherit one X chromosome from your mother and one X or Y chromosome from your father, which is what determines your sex.
A certain inheritable genetic condition can be recessive or dominant. If it's dominant, it shows even if just one chromosome carries that condition. If it's recessive, it has to be in both ones (or just the x one or just y if you're male. That's why some conditions, such as daltonism, affect men more that women).
For example, blue eyes are a recessive trait, brown eyes are a dominant trait. If your parents are both blue eyed, you will surely have blue eyes as well. The same can't be said if both of your parents have brown eyes: they might still be carrier of the blue eyed trait (both of them have to), in which case you would have a 25% chance (1/4) to have blue eyes (½ to inherit the carrier chromosome from your mother; ½ from your father). The same can be said about albinism
