You plan to redo the test cross and need to decide how many

You plan to redo the test cross, and need to decide how many F1 offspring to look at. You know that if you see any wrinkled offspring, the unknown was Rr. However, if you see only round offspring, the unknown could be RR or Rr. From the first two parts of the question, you know that the more round offspring you get, the lower n the probability that the unknown is Rr. How many round offspring would you have to get so that the probability that the unknown plant is Rr is so low that you would instead conclude that it is an RR plant? The cutoff you\'ve set is 5% (i.e. if the probability of producing n round offspring from a heterozygous parent is 5% or less, a different explanation is better)? Your answer must be an integer [you can\'t look at partial seeds!]. Answer:

Solution

100% round offspring we will have to get for low probability of unknown Rr plants

if RR or Rr =Round seeds

RR cross Rr

genotype 50% ROUND with RR

50% Round with Rr

Phenotype 100% Round