Using a Punnett Square. A Punnett Square can help determine the probability that offspring will have a particular phenotype or genotype. Example: The possible offspring outcomes for parents who are both carriers of a cystic fibrosis mutation.
Pyrokinesis is an alleged psychic ability allowing a person to create and control fire with the mind. There is no conclusive evidence that pyrokinesis is a real phenomenon. Alleged cases are said to be hoaxes, the result of trickery.
Definition of Pyoderma gangrenosum. Pyoderma gangrenosum: An ulcerating condition of skin that results in heaped borders with a typical appearance. Pyoderma gangrenosum appears to be mediated by the immune system, but the exact cause is unknown. The lesion usually begins as a soft nodule on the skin that then ulcerates. The ulcer enlarges, and the skin at the edge is purple-red.