CROSSES (WITH LARGE PROGENIES) AND PEDIGREES

Today we looked at how to use phenotypes of parents and their offsprings to determine:

- the mode of inheritance of the traits in question (what is dominant to what, and whether the traits are autosomal or sex-linked);

- the respective genotypes of parents and various individuals in the offspring.

More info on pedigrees on the paper-saving page...(see link on the right).

For better results in 334, remember to:

- define your symbols, if you introduce any (e.g. if you decide to use "L" for "long" and "l" for "short", indicate so)

- justify your answers, for example by showing that if you give your individuals the genotypes that you claim are the correct ones, and you do the crosses indicated in the question, you obtain the same result as that indicated in the question.

- be consistent... if you claim that A is dominant to a, this has to be true for the whole question! You can't switch halfway through...

On Thursday we'll do some pedigrees with probabilities and some work to relate meiosis to Punnett's squares and crosses.

Cheers

Pam