Punnett SquaresTo my left is an example of a punnett square. Punnett squares calculate the percentage chance of the trait between male and female intercourse or breeding. For example, the picture on the left show one black and one chocolate Labrador. As you can see each dog have 2 letters either capital or lower case. These letters are called alleles, which determine what trait you the dog will get (Black or Chocolate). The Black dog for example has "Bb". The capital B represents it's dominant and the lowercase b represents it's recessive. In this case the uppercase means black and lowercase means chocolate. The male Dog will always be the letters on top of the square, while the female is the on the left side. To tell what the new born pup(ies) will turn out to be, you just connect the letters to the designated square. for example the top left corner of the square would be "Bb". Remember the uppercase latter always goes in front because it's dominant. This process continues til it's finished. The final out come of it becomes 2 black and 2 chocolate Labrador. "Bb" means Heterozygus , which means both alleles are different, but since the capital "b" is there , it will still be a dominant trait. "bb" by itself means Homozygus recessive because both of the alleles are recessive. Same goes for "BB", which means that it will be Homozygus dominant because it has both dominant alleles.
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Codominace and IncompleteAs in relation to the punnett square, sometimes when breeding you don't actually get the male and female traits. Sometimes you actually get either the traits combined or both the traits show up at once. Codominace is when both the traits of the male and female dog show up on their off spring like the example of the picture on the bottom. Incomplete means that both the male and female traits are combined and made into one. For example if one dog was white and one dog was black, the off spring would be grey.
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