You have a cucumber plant that produces open flowers But you

You have a cucumber plant that produces open flowers. But you do not know if it is homozygous or if it carries one copy of the recessive allele that leads to closed flowers (see questions #3 above). Propose an experiment that would allow you to infer the genotype of this individual. In your answer, include a description of the expected results and how you would interpret them. You can assume that you have access to other plants of known genotype for your experiment.

Solution

Crossing this plant with a plant with recessive allele will result in progeny that will lead to identification of whether the plant is homozygous or carries one copy of the recessive allele( heterozygous).

Let \'C\' be the allele for open flowers and \' c \' be the allele for closed flowers.

cross 1 If the plant is homozygous then

CC ( open flowers) (test plant) X cc ( closed flowers)

progeny Cc( all open flowers)

RESULT - IF THE PLANT IS HOMOZYGOUS THEN ITS CROSS WITH A RECESSIVE PLANT WILL PRODUCE PLANT PROGENY WITH ALL OPEN FLOWERS

cross 2- If the plant is heterozygous

Cc( open flower) (test plant) X cc( closed flower)

progeny 2 Cc ( open flower) : 2 cc( closed flower) .

IF THE PLANT IS HETEROZYGOUS THAT IS IF IT CARRIES ONE RECESSIVE ALLELE, THEN ITS CROSS WITH HOMOZYGOUS RECESSIVE PLANT WILL PRODUCE OPEN FLOWERS AND CLOSED FLOWERS PROGENY IN 1:1 RATIO.