1) You have been given three plants: two produce solid black orchids, and one has grey petals. You cross each black-flowered plant to the grey plant with the following results
black #1 X grey 87 solid black, 83 spotted black
black #2 X grey all black
You cross the solid black-flowered F1 plants from cross #2 with the following results in the F2:132 black35 spotted black11 greyDevise the best genetic explanation for these results.
How many genes are involved in these phenotypes?
2) Horses can be cremello (light cream color), chestnut (a brownish color) or palomino(golden color with white in the horse’s tail and mane). Of these phenotypes, only palominos never breed true.
Parents F1 Progeny
(A) Cremello x Palomino 1/2 cremello & 1/2 palamino
(B) Chestnut x Palomino 1/2 chestnut & 1/2 palomino
(C) Palomino x Palomino 1/4 chestnut, 1/4 cremello, 1/2 palomino
How many genes are involved in these results?
3) You have isolated a pure breeding strain of flies with black bodies (strain #1). The black allele is recessive to the wild-type brown allele. Another lab has also isolated a pure breeding strain with a recessive black allele (strain #2). You cross males from your strain #1 with females from strain #2. All of the F1 progeny have wild-type brown bodies. You cross the F1 sons and daughters to each other and see the following F2 progeny:
(640 total offspring)
How many genes are involved in these crosses?
4) In a cross of Rr X Rr, what is the chance of getting 5 rr plants?[enter your answer as a fraction such as 1/9 or 1/100000]