Observing Similarities and Differences in Phenotypes Among Family Members

For this week's assignment please jot down the most obvious similarities in physical characteristics and behavior for several children and parents whom you know well (for example, height, weight, eye and hair color, personality, interests, hobbies).

Did they find that one child shows combined features of both parents, another resembles just one parent, or another is unlike either parent?

Next, please trace a visible genetic trait (phenotype), such as hair or eye color, through as many of their family members aspossible. When the genetic family tree is complete, try to determine genotypes. Note that you must begin with the most recent generation and work back. Also note that inferences must be made because homozygosity and heterozygosity cannot be determined for some dominant traits. For example, it may not be known whether someone is homozygous for dark hair orheterozygous-that is, a genetic makeup consisting of a dominant dark-hair and a recessive light-hair gene.

Please explain how differences among family members in the first activity may have occurred. Integrate the terms phenotype,genotype, and meiosis into the discussion.