What organ do we use to store air/breathe?

What are the student's observations and inferences before he starts his investigation?

Which of the following is an eon in the time scale? phanerozoic proterozoic archean all of the above

3. in the fruit fly, recessive mutation brown, b, causes brown color of the eye and absence of red pigment. recessive mutation p of another independent gene causes purple color of the eye and absence of brown pigment. the cross of a brown-eyed female and purple-eyed male produced wild type eyes. what will be the colors and their ratio in f2?