Quote:
Originally Posted by ChainLegacy
Though in light of this fact, I'm confused as to how some traits can skip generations?  |
1.) Genes are inherited from both the mother and the father. Humans are diploid organisms, meaning two genes for every trait. One is from the mother, and one is from the father.
2.) Having the gene for a trait does not mean the person will have that trait. There are dominant and recessive genes for traits. A dominant gene will be expressed as a trait, even if the person only has one dominant gene in a pair. A recessive gene will not be expressed as a trait unless the dominant gene is not present, meaning all genes for the trait are recessive. This is how some traits skip generations. Some traits are recessive and do not activate because the dominant gene takes precedence.
3.) Keep in mind that while humans are diploid (paired genes), sex cells are haploid (single genes). Going back to #1, there is no telling which gene the child could have inherited from their parents. If the parent is heterozygous (dominant gene paired with recessive) for a trait, the child could have inherited either gene. In the unlikely case, the child could inherit the recessive gene from both parents who are heterozygous dominant for a trait. That is how you could possibly have brown hair, brown eyed parents (yes, brown/black is the dominant hair/eye color) having a blonde hair, blue eyed child.